calm, cool, and collected; level and calm
untalkative; quiet; taciturn; reticent; uncommunicative
willingly; voluntarily; on one's own accord
stage; step; level; rank; order; stairs
special; particular; peculiar; unique
excitement; stimulation; agitation; arousal
nature (of a person); sex; gender; sex (i.e. sexual attraction, activity, etc.); gender; -ty
transmission (e.g. news, chemical signals, electricity); communication; delivery; conveyance; transfer; relay
material; substance; matter
nature; natural; spontaneous; naturally; spontaneously
accumulation; accumulate; store
goes without saying; needless to say; obvious
(right at the) side; just beside
running parallel (to); running side-by-side; keeping pace (with)
to nod; to bow one's head in assent; to agree
popular name; common name; nickname; alias
term; terminology; wording; choice of words; phraseology
fight; battle; combat; struggle (for rights, higher wages, etc.); strife; (labor) dispute
flight; desertion; escape
origin of a word; derivation of a word; etymology
autonomic nervous system; ANS
to hinder; to obstruct; to disrupt; to interfere with; to cause a delay
observation; survey; measurement; opinion; prediction; thinking
composition; constitution
analysis; analytical study; parsing; parse
extraction; abstraction; selection (from a group); sampling
possible; potential; practicable; feasible
in spite of; nevertheless; although; despite; no matter the; regardless of
riddle; puzzle; enigma; enigmatic; mysterious
chemical substances; chemicals
pattern; behavioural pattern; behavioral pattern; predictability
breaking through; breakthrough; surmounting; overcoming; exceeding; passing
another; one more; not quite; not very good; lacking
degree (angle, temperature, scale, etc.); counter for occurrences; strength (of glasses); glasses prescription; alcohol content (percentage); alcohol by volume; extent
to examine; to look up; to investigate; to check up; to sense; to study
purposely (of something needless, unexpected or seemingly counterproductive, etc.); daringly (doing something); not necessarily; not particularly; (arch.) definitely not