Keyword
blue
Info
FrequencyTop 400-500
Type
Kyōiku (1st grade) 
?
KankenLevel 10
Heisig1654
Readings
あお
(60%)
せい
(34%)
さお
(2%)
Composed of
king with a hat
moon
Mnemonic

If a king with a hat would live on the moon, he would certainly appear blue due to all of the blue light reflected off Earth.

Used in kanji (9 in total)
emotion
spirit (of life)
quiet
clear up
Used in vocabulary (379 in total)
blue; azure; green; pale; gray; unripe
blue; azure; green; green light (traffic); black (horse coat color); blue 5-point card; immature
youth; young man
to become pale; to turn pale
pale; pallid; bluish-white
youth; springtime of life; adolescent
deep blue; bright blue; ghastly pale; pallid; white as a sheet
to become blue; to turn green; to turn pale; to blanch (with fear)
lush mountain; green mountain; grave; burial place
verdant; fresh and green; bright green; lush
vein (esp. in head)
Japanese laurel; spotted laurel; Aucuba japonica; live tree
inexperienced; immature; green; grassy-smelling; smelling of raw vegetation
fresh leaves
tattoo (esp. a traditional Japanese one); tattooing
black with hints of blue (as in a bruise); bluish black
handsome young man; Adonis
youth; young person
good young man; agreeable youth
bluish; tinged with blue
Aomori (city, prefecture)
blueness; greenness; tinge of blue; (vegetable) garnish
green youth; immature youth; novice; greenhorn
blue dragon (an auspicious creature in Chinese mythology); Azure Dragon (god said to rule over the eastern heavens)
light blue; pale blue
to become pale; to turn pale
ultramarine colour (color)
one's youth; one's youthful days (years); the flower of one's youth; the springtime of one's life
green willow (i.e. one that has budded); meat of the trough shell (Mactra chinensis)
bluebird of happiness
Aomori prefecture (Tōhoku area)
blue dragon (an auspicious creature in Chinese mythology); Azure Dragon (god said to rule over the eastern heavens)
celadon porcelain
Qingdao (China); Tsingtao; Chingtao
holding one's sword pointing towards the opponent's eyes (kendo stance); warm, welcoming eyes
verdigris; green rust; copper rust
deep blue sky; bottomless blue sky
(one's) youth; one's younger days
young persons' association
green bamboo
potassium cyanide
bluish-green; turquoise; aqua
deep blue; bright blue; ghastly pale; pallid; white as a sheet
green paddy
green light (traffic); green light; go-ahead signal; permission to go ahead (with something)
unripe plum
blue-green; turquoise; aqua; (arch.) spirogyra; (arch.) algae forming pond scum
hydrocyanic acid; prussic acid; hydrogen cyanide
deep blue; bright blue; ghastly pale; pallid; white as a sheet
green grass
blue cloth; blue ground; blue background
blueprint; cyanotype; blueprint (for the future); plan
(horned) blue demon; blue ogre
aojiru; vegetable juice drink made from green leafy vegetables
Prussian blue; deep blue; dark blue; ultramarine
wind blowing through fresh verdure; mountain air
cabbageworm (caterpillar of the cabbage white butterfly)
blue sky; skyrocketing (of prices); having no limit; the sky being the limit
blueness; greenness; tinge of blue; (vegetable) garnish
indigo blue
sapphire; jacinth
vegetables; (edible) greens; blueback (any fish with a bluish back, such as the Japanese sardine)
greengrocer; fruit and vegetable shop
blue and white; paleness; pallidness
young literary enthusiast
inexperienced; immature; green; grassy-smelling; smelling of raw vegetation
bluish stone; greenish stone; blue-tinged tuff
having sex outdoors
fruit(s) and vegetables; produce
blueback (any fish with a bluish back, such as the Japanese sardine)
blue sky; erudition; detachment from the world; high rank
medium-grade millstone
speculatively buying a rice harvest, while the fields are still green; recruiting of university students before the agreed date
Japanese rat snake (Elaphe climacophora)
bluish sheen; steel-blue sheen
large green soybean; green peas
asphalt; bitumen
young persons' association
the blues; bluish colors
(written) history
celadon green; pale sea-green
blue eyes; a Westerner
green laver (Enteromorpha); green dried seaweed; nori
Chinese parasol-tree (Firmiana simplex); Chinese-bottletree; Japanese varnishtree; phoenix-tree
grayish blue; greyish blue
puberty; adolescence; youth
black (horse coat color)
green calabash; unripe gourd; scrawny, pale person; sallow-faced person
bluestocking
light blue; ice blue; sky blue; powder blue
the grass is always greener on the other side of the fence
Chinese-style stir-fry containing green peppers and meat; pepper steak (US)
blue mold; blue mould; penicillium
bluish; tinged with blue
use of blue eyebrow pencil to indicate a character has shaved his cheeks (in kabuki)
green spring onion
green (tree) frog
green calabash; unripe gourd; scrawny, pale person; sallow-faced person
light blue; pale blue
5-point card with a blue tanzaku; blue ribbon card; scoring combination consisting of the three 5-point cards with blue tanzaku
officially sanctioned brothel (Edo-period)
grey heron (Ardea cinerea); gray heron
Japanese rhodea (plant of the lily family); Rhodea japonica
pale; pallid; bluish-white
being cleared of all the charge (brought against one); being found completely innocent
Prussian blue; deep blue; dark blue; ultramarine
feeling sad or downhearted; down in the dumps
harvesting rice while it is still green; recruiting of university students before the agreed date
Sirius (star in the constellation Canis Major); Alpha Canis Majoris; the Dog Star
dark-colored horse with a lustrous coat (coloured); white horse
youthful crowd; crowd of young people coming into their own
green beefsteak plant; green perilla
blue line; area around a red-light district where illegal prostitution occurred (marked on police maps by a blue line) (1940s-1956); non-legal public waterway (denoted by a blue line on cadastral maps; sometimes no longer physically existing)
green beefsteak plant; green perilla
open-air market; outdoor market
snake (esp. Japanese rat snake)
grey tinged with green; grey tinged with blue
red and blue; paints; colors; painting; picture
brown (horse coat color)
fruit and vegetable market
green crop; green vegetable
verdant; fresh and green; bright green; lush
wet behind the ears; inexperienced; immature
seigaiha; wave pattern
the grass is always greener on the other side of the fence
training and accommodation institution for young men
bluish; greenish; immature; inexperienced; green
greenish-black earth; green verditer; dark green tinged with yellow
celestite; celestine
ramie fibre (fiber)
outing in spring
blueprint; cyanotype
blue return; blue-paper income-tax return; type of income tax return filing which allows for special income deductions
bluebottle fly; (arch.) little pest
blue eyebrow pencil; blue eyebrows; deep blue; dark blue
tattooist; tattoo artist; tattooer
dropsical (blue-green) swelling
a bolt out of the blue
fruit and vegetable market
ramie fibre (fiber)
vegetable shop; greengrocery; seller of vegetables
Litsea cubeba
greenish nasal mucus; green snot
blue tag; blue card; blue ticket; batons (playing card suit in traditional Japanese gambling decks)
bok choy (Brassica rapa subsp. chinensis; esp. cultivars with green stalks); pak choi; Chinese cabbage
blue light (e.g. of LED); blue glow; cadmium blue
Ilex macropoda (species of holly common in Japan)
5-point card with a blue tanzaku; blue ribbon card; scoring combination consisting of the three 5-point cards with blue tanzaku
shortfin mako shark (Isurus oxyrinchus)
spirogyra; algae forming pond scum
goddess of frost and snow; frost and snow
the student has become the master; (lit.) blue dye comes from the indigo plant and is bluer than indigo
greenish nasal mucus; green snot
Blue Sky with a White Sun; party flag and emblem of the Kuomintang (Chinese Nationalist Party)
the Blue House (South Korea's presidential palace)
greenish nasal mucus; green snot
beautiful stretch of sandy beach dotted with pine trees; (lit.) white sand, green pines
dark blue; deep blue; navy blue
parking on the street; curbside parking; kerbside parking; unauthorized parking outdoors
ceramics with a blue pattern on a white background
wet behind the ears; inexperienced; immature
ceramics with a blue pattern on a white background
flesh of a blueback fish
blue-green; malachite green; color of green bamboo
emperor moth (Actias artemis); Japanese moon moth
blue mold; blue mould; penicillium
5-point card with a blue tanzaku; blue ribbon card; scoring combination consisting of the three 5-point cards with blue tanzaku
green spring onion
greenish nasal mucus; green snot
bluebottle fly; (arch.) little pest
dropsical (blue-green) swelling
lush mountain; green mountain
blue mold; blue mould; penicillium
blue traffic violation ticket (designating a minor violation); second-class ticket
fruit and vegetables; greengrocery
blue registration plate with white characters (used for diplomatic vehicles); diplomatic vehicle registration plate
Mariko Aoki phenomenon; phenomenon of feeling an urge to defecate when stepping inside a bookstore
lush waterside reeds
Blue Sky, White Sun, and a Wholly Red Earth; flag of the Republic of China
Seishun 18 ticket; seasonally available railway ticket for 5 days of unlimited travel on non-Shinkansen JR trains
Seishun 18 ticket; seasonally available railway ticket for 5 days of unlimited travel on non-Shinkansen JR trains
Blue Book (government-issued report)
green beefsteak plant; green perilla
green flesh (melon, etc.); green meat (e.g. discolored tuna meat)
green youth; immature youth; novice; greenhorn
area around a red-light district where illegal prostitution occurred (marked on police maps by a blue line) (1940s-1956)
anxious or pained sigh
armchair intellectual
Seishun 18 ticket; seasonally available railway ticket for 5 days of unlimited travel on non-Shinkansen JR trains
blue light-emitting diode; blue LED
minor; not of age
brown hawk owl (Ninox scutulata)
blue ballot (representing an opposition vote)
area around a red-light district where illegal prostitution occurred (marked on police maps by a blue line) (1940s-1956)
green tassel hung above the northeast corner of the ring
argus pheasant (Argusianus argus)
green spring onion
the grass is always greener on the other side of the fence
cultivar of Japanese apricot (Prunus mume); cultivar of mulberry
man of perennial youth; man who never loses his youthful vigor
blueprint; cyanotype
electric blue; steel blue
youthful ardor; rash impulse of an inexperienced youth
Harbin pear (Pyrus ussuriensis var. hondoensis); Ussurian pear; Chinese pear
Young Italy (19th century political movement)
phosphor bronze
Aomori Nebuta Festival (August 2-7)
greenish nasal mucus; green snot
Aomori Nebuta Festival (August 2-7)
pre-harvest estimate of a rice field's yield and selling price
blue eyes; a Westerner
Qinghai Province (China)
Paris green; emerald green
powderized green laver; blue-green algae (esp. Microcystis spp.); cyanobacteria; algal bloom; water bloom
5-point card with a blue tanzaku; blue ribbon card; scoring combination consisting of the three 5-point cards with blue tanzaku
white-bellied green pigeon (Treron sieboldii)
sleeping under the stars; having sex outdoors
green laver (Enteromorpha); green dried seaweed; nori
mantis shrimp (any marine crustacean of order Stomatopoda, esp. the species Oratosquilla oratoria)
deep blue; ghastly pale
asphalt; bitumen
spirogyra; algae forming pond scum
spirogyra; algae forming pond scum
5-point card with a blue tanzaku; blue ribbon card; scoring combination consisting of the three 5-point cards with blue tanzaku
budgerigar (Melopsittacus undulatus); common pet parakeet; shell parakeet; budgie
greenbottle fly (esp. species Lucilia caesar)
greenbottle fly (esp. species Lucilia caesar)
dropsical (blue-green) swelling
seigaiha; wave pattern
Scarus ovifrons (species of parrotfish)
Ilex macropoda (species of holly common in Japan)
green turtle (Chelonia mydas)
brown hawk owl (Ninox scutulata)
Seishun 18 ticket; seasonally available railway ticket for 5 days of unlimited travel on non-Shinkansen JR trains
Chinese flowering ash (Fraxinus lanuginosa form. serrata)
Parabenzoin praecox
lush waterside reeds
Mariko Aoki phenomenon; phenomenon of feeling an urge to defecate when stepping inside a bookstore
blue; azure; green; pale; gray; unripe
blue jay (Cyanocitta cristata)
black carp (Mylopharyngodon piceus)
forest green tree frog (Rhacophorus arboreus)
Aucuba japonica var. borealis (variety of Japanese laurel)
Schlegel's green tree frog (Rhacophorus schlegelii)
chaffinch (Fringilla coelebs)
pre-harvest estimate of a rice field's yield and selling price
Aleutian mountainheath (Phyllodoce aleutica)
Hypselodoris festiva (species of sea slug)
greenshank (species of sandpiper, Tringa nebularia)
Yangqingquan; Yangqing Fist
blueprint
blackish blue
failing to ripen or blossom
bacterial wilt (caused by the bacteria Ralstonia solanacearum)
bacterial wilt (caused by the bacteria Ralstonia solanacearum)
blue telephone; (blue) public telephone
poisonous algae bloom (often green in color) (colour)
dealing in unharvested rice crop
young girl unused to the ways of the world; woman not serving in the imperial court
Asiatic dayflower (Commelina communis); dayflower blue dye
shaved head; person with a shaved head
home is wherever one lays one's hat; you can make your living anywhere in this world; there's room for us all in the world; (lit.) wherever there are humans, there are burial places
home is wherever one lays one's hat; you can make your living anywhere in this world; there's room for us all in the world; (lit.) wherever there are humans, there are burial places
home is wherever one lays one's hat; you can make your living anywhere in this world; there's room for us all in the world; (lit.) wherever there are humans, there are burial places
home is wherever one lays one's hat; you can make your living anywhere in this world; there's room for us all in the world; (lit.) wherever there are humans, there are burial places
home is wherever one lays one's hat; you can make your living anywhere in this world; there's room for us all in the world; (lit.) wherever there are humans, there are burial places
Spanish fly (Lytta vesicatoria)
Bluetooth (variety of short-range wireless LAN)
the people; the public; citizenry
queen coralbead (Cocculus orbiculatus)
blue-stocking ladies
Prussian blue
asphalt rock; asphalt stone; bituminous rock; rock asphalt
navy blue demon residing in hell
mackerel (esp. the chub mackerel, Scomber japonicus)
soy flour made from parched green soybeans
soy flour made from parched green soybeans
soy flour made from parched green soybeans
cyanide process
fruit harvested before it's ripened
spiderwort-dyed paper (used for making a rough sketch when dyeing)
liquid seasoning made from leaf vegetables mixed with sake, mirin, sugar, etc.
dark indigo tinged with brighter blue
bright yellow-green tinged with grey
maple tree not yet turned red; kasane color combination (green at front and russet behind)
green mandarin; mandarin variety that can be eaten while the skin is green
salad of fish and vegetables, dressed with crushed mustard leaves and greens seasoned with sake lees, miso and vinegar
salad of fish and vegetables, dressed with crushed mustard leaves and greens seasoned with sake lees, miso and vinegar
fenqing; leftist Chinese youth (usu. nationalistic)
(written) history
blue letter style; comparatively mature fashion style named after fashion magazines featuring it (whose cover titles are printed in blue)
Mohammedan blue (pigment used in porcelain painting)
Abdim's stork (Ciconia abdimii); white-bellied stork
methylene blue
tattoo; tattooing
wide open sky; the blue; heavens; firmament
Japanese flowering ash (Fraxinus sieboldiana)
rainbow lorikeet (Trichoglossus haematodus); rainbow lory
Maries' fir (Abies mariesii)
European greenfinch (Carduelis chloris)
bluespotted cornetfish (Fistularia commersonii)
Chlorophthalmus albatrossis (species of greeneye)
blue-winged skipper butterfly
blue-winged skipper butterfly
blue-gray snapper (Aprion virescens); green jobfish
ragfish (Icosteus aenigmaticus)
Chlorophthalmus borealis (species of greeneye)
aoganpi (Wikstroemia retusa); ganpi
small-scale whiting (Sillago parvisquamis); blue whiting
Epipactis papillosa (species of orchid)
red-root amaranth (Amaranthus retroflexus); redroot pigweed; red-rooted pigweed; common amaranth; pigweed amaranth; common tumbleweed
gutweed (Ulva intestinalis); grass kelp
great morinda (Morinda citrifolia); Indian mulberry; noni; beach mulberry; cheese fruit
scoring combination consisting of the June, September, and October 5-point cards
Examples (200 in total)
That girl's eyes are blue.
That blue one is also mine.
This building is blue.