It is the hypothetical source of/evidence for its existence is provided by: Sanskrit cyavate "stirs himself, goes;" Greek kinein "to move, set in motion; change, stir up," kinymai "move myself;" Latin ciere (past participle citus, frequentative citare) "to set in motion, summon;" Gothic haitan "call, be called;" Old English hatan "command, call."
in the names of sciences or disciplines (acoustics, aerobics, economics, etc.), a 16c. revival of the classical custom of using the neuter plural of adjectives with Greek -ikos "pertaining to" (see -ic) to mean "matters relevant to" and also as the titles of treatises about them. Subject matters that acquired their English names before c. 1500, however, tend to be singular in form (arithmetic, logic, magic, music, rhetoric). The grammatical number of words in -ics (mathematics is/mathematics are) is a confused question.
<a href="https://www.etymonline.com/word/kinesics">Etymology of kinesics by etymonline</a>
Harper, D. (n.d.). Etymology of kinesics. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/kinesics