Word Origin & History
friendO.E. freond, prp. of freogan "to love, to favor," from P.Gmc. *frijojanan "to love" (cf. O.N. frændi, O.Fris. friund, M.H.G. friunt, Ger. Freund, Goth. frijonds "friend," all alike from prp. forms). Related to O.E. freo "free." Meaning "a Quaker" (a member of the Society of Friends) is from 1670s.
Feond ("fiend," originally "enemy") and freond often were paired alliteratively in O.E.; both are masculine agent nouns derived from prp. of verbs, but are not directly related to one another. Related: Friends. As a verb, in the Facebook sense, attested from 2005.