collet n.

c. 1300, coler, coller, "neck armor, gorget, something worn about the neck," from Old French coler "neck, collar" (12c., Modern French collier), from Latin collare "necklace, band or chain for the neck," from collum "the neck," from PIE *kwol-o- "neck" (source also of Old Norse and Middle Dutch hals "neck"), literally "that on which the head turns," from root *kwel- (1) "revolve, move round."

The spelling was re-Latinized in early modern English. From late 14c. as "border at the neck of a garment," also "band put around the neck of a dog or other animal for purposes of restraint or identification." From mid-15c. as "neck-band forming part of the harness of a horse or other draught-animal."

also *kwelə-, Proto-Indo-European root meaning "revolve, move round; sojourn, dwell."

It forms all or part of: accolade; ancillary; atelo-; bazaar; bicycle; bucolic; chakra; chukker; collar; collet; colonial; colony; cult; cultivate; culture; cyclamen; cycle; cyclo-; cyclone; cyclops; decollete; encyclical; encyclopedia; entelechy; epicycle; hauberk; hawse; inquiline; Kultur; lapidocolous; nidicolous; palimpsest; palindrome; palinode; pole (n.2) "ends of Earth's axis;" pulley; rickshaw; talisman; teleology; telic; telophase; telos; torticollis; wheel.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit cakram "circle, wheel," carati "he moves, wanders;" Avestan caraiti "applies himself," c'axra "chariot, wagon;" Greek kyklos "circle, wheel, any circular body, circular motion, cycle of events,"polos "a round axis" (PIE *kw- becomes Greek p- before some vowels), polein "move around;" Latin colere "to frequent, dwell in, to cultivate, move around," cultus "tended, cultivated," hence also "polished," colonus "husbandman, tenant farmer, settler, colonist;" Lithuanian kelias "a road, a way;" Old Norse hvel, Old English hweol "wheel;" Old Church Slavonic kolo, Old Russian kolo, Polish koło, Russian koleso "a wheel."