amicus curiae

fem. proper name, from Old French Amee, literally "beloved," from fem. past participle of amer "to love," from Latin amare "to love, be in love with; find pleasure in," Proto-Italic *ama- "to take, hold," from a PIE root meaning "take hold of," also the source of Sanskrit amisi, amanti "take hold of; swear;" Avestan *ama- "attacking power;" Greek omnymi "to swear," anomotos "under oath;" Old Irish namae "enemy." According to de Vaan, "The Latin meaning has developed from 'to take the hand of' [to] 'regard as a friend'."

c. 1600, one of the ten divisions of each of the three ancient Roman tribes; also "the Senate-house of Rome," from Latin curia "court," perhaps from *co-wiria "community of men" (from PIE root *wi-ro- "man"). The sense was transferred to the papal court (by 1825). Related: Curial.