Meaning

noun either of the rudimentary hind wings of dipterous insects; used for maintaining equilibrium during flight

originFrom Ancient Greek ἁλτῆρες (haltêres, “weights held in the hand to give an impetus in leaping”). Note that in the original Greek, there seems to have been no singular for ἁλτῆρες (haltêres), and some authorities maintain that halteres is a plurale tantum, but in English entomological usage, haltere sometimes appears as a back-formation. Sometimes the singular halter is used instead, but this may…

Etymology from Wiktionary, CC BY-SA 3.0