horsefly/ˈhoɹsˌflaɪ/EtymologyFrom Middle English horse fliȝe, equivalent to horse + fly.nounAny of several medium to large flies, of the family Tabanidae, that suck the blood of mammals (not to be confused with Stomoxys calcitrans, the stable fly, or dog fly).“It was not a horsefly and it was not a deerfly; it was bigger than either.”