haltere
noun
hal·tere ˈhȯl-ˌtir 
ˈhal-
plural halteres ˈhȯl-ˌtirz
ˈhal-;
hȯl-ˈtir-ēz,
hal-
: one of a pair of club-shaped organs in a dipteran fly that are the modified second pair of wings and function as sensory flight stabilizers
Word History
Etymology
New Latin halter, from Latin, jumping weight, from Greek haltēr, from hallesthai to leap — more at sally
First Known Use
circa 1823, in the meaning defined above