Flock
Old English flocc, of unknown origin. The original sense was ‘a band or body of people’: this became obsolete, but has been reintroduced as a transferred use of the sense ‘a number of animals kept together’.
wiktionary
From Middle English flok, from Old English flocc(“flock, company, troop”), from Proto-Germanic *flukkaz, *flakka-(“crowd, troop”). Cognate with Middle Low German vlocke(“crowd, flock”), Old Norse flokkr(“crowd, troop, band, flock”). Perhaps related to Old English folc(“crowd, troop, band”). More at folk.
From Middle English flok(“tuft of wool”), from Old French floc(“tuft of wool”), from Late Latin floccus(“tuft of wool”), probably from Frankish *flokko(“down, wool, flock”), from Proto-Germanic *flukkōn-, *flukkan-, *fluksōn-(“down, flock”), from Proto-Indo-European *plewk-(“hair, fibres, tuft”). Cognate with Old High German flocko(“down”), Middle Dutch vlocke(“flock”), Norwegian dialectal flugsa(“snowflake”). Non-Germanic cognates include Albanian flokë(“hair”).
etymonline
flock (n.1)
Old English flocc "a group of persons, company, troop," related to Old Norse flokkr "crowd, troop, band," Middle Low German vlocke "crowd, flock (of sheep);" of unknown origin, not found in other Germanic languages; perhaps related to folc "people," but the metathesis would have been unusual for Old English.
In Old English of humans only; extended c. 1200 to "a number of animals of one kind moving or feeding together;" of domestic animals c. 1300. The special reference to birds is recent (19c.). Transferred to bodies of Christians, in relation to Christ or their pastor, from mid-14c.
flock (n.2)
"tuft of wool," mid-13c., also found in continental Germanic and Scandinavian, all probably from Old French floc, from Latin floccus "tuft of wool, lock of hair," a word of unknown origin.
flock (v.)
c. 1300 "gather, congregate" (intransitive), from flock (n.1). Related: Flocked; flocking.
