Negotiation
late 15th century (denoting an act of dealing with another person): from Latin negotiatio(n- ), from the verb negotiari (see negotiate).
wiktionary
Borrowed from Middle French négociation, or from Latin negotiatio(“the carrying on of business, a wholesale business”), from negotiari(“to carry on business”); see negotiate.
etymonline
negotiation (n.)
early 15c., negotiacioun, "a dealing with people, trafficking," from Old French negociacion "business, trade," and directly from Latin negotiationem (nominative negotiatio) "business, traffic," noun of action from past participle stem of negotiari "carry on business, do business, act as a banker," from negotium "a business, employment, occupation, affair (public or private)," also "difficulty, pains, trouble, labor," literally "lack of leisure," from neg- "not" (from PIE root *ne- "not") + otium "ease, leisure," a word of unknown origin.
The sense expansion from "doing business" to also include "bargaining" about anything took place in Latin. Meaning "mutual discussion and arrangement of the terms of a transaction or agreement" is from 1570s.
