guess; speculation; supposition
surface-to-air missile; SAM
unidentified flying object; UFO
to take (someone) away; to carry off; to abduct; to kidnap
error; mistake; slip; bug
delay; lag; postponement; falling behind
idle time; down time; window period
low-altitude flying; having consistently poor results (grades, sales, etc.); barely scraping by; being on the verge of failing
nonexistent; nil; none; nothing (at all); bugger-all
whole area; whole region; stretch (of land); tract; belt
observation; survey; measurement; opinion; prediction; thinking
class (e.g. school); grade; rank; kyū; kyu; junior rank in martial arts, go, shogi, etc.
reconnaissance satellite; spy satellite
flaw; defect; problem; inconvenient
official; formal; formula (e.g. mathematical); official (social media) account (of a company, organization, etc.)
sixteenth day of the month; sixteen days
meaning; point (e.g. of a statement); gist; effect
information; (brief) notice; letting someone know; first report; initial report
fifteenth day of the month; fifteen days
break (in the weather, esp. rain or snow); interval of clear weather; patch of blue sky; (arch.) period of serenity
so what!; who gives a damn?
mass communication; mass media
even if; (it doesn't matter) whether (A or B or ...); whatever; should