Session

google

ref

late Middle English: from Old French, or from Latin sessio(n- ), from sess- ‘seated’ (see sessile).

wiktionary

ref

From Middle English session, from Old French session, from Latin sessiō(“a sitting”), from sedeō(“sit”).

etymonline

ref

session (n.)

late 14c., "periodical sitting of a court," from Old French session "act or state of sitting; assembly," from Latin sessionem (nominative sessio) "act of sitting; a seat; loitering; a session," noun of action from past participle stem of sedere "to sit" (from PIE root *sed- (1) "to sit"). Sense of "period set aside for some activity" is first recorded 1920, in bull session, probably from quarter sessions courts (see quarter (n.1)). Musical sense of "recording occasion in a studio" is from 1927.