'Lug wrench' definitions:

Definition of 'lug wrench'

noun

A wrench with jaws that have projecting lugs to engage the object that is to be rotated

From: GCIDE

Lug \Lug\ (l[u^]g), n. [Sw. lugg the forelock.]
1. The ear, or its lobe. [Scot. & Prov. Eng.] [1913 Webster]
2. That which projects like an ear, esp. that by which anything is supported, carried, or grasped, or to which a support is fastened; an ear; as, the lugs of a kettle; the lugs of a founder's flask; the lug (handle) of a jug. [1913 Webster]
3. (Mach.) A projecting piece to which anything, as a rod, is attached, or against which anything, as a wedge or key, bears, or through which a bolt passes, etc. [1913 Webster]
4. (Harness) The leather loop or ear by which a shaft is held up. [1913 Webster]
5. (Zool.) The lugworm. [1913 Webster]
6. A man; sometimes implying clumsiness. [slang] [PJC]
Lug bolt (Mach.), a bolt terminating in a long, flat extension which takes the place of a head; a strap bolt.
Lug nut (Mach.), a large nut fitting a heavy bolt; -- used especially of the nuts used to attach wheels to vehicles.
Lug wrench (Mach.), a wrench used to tighten or loosen lug nuts, usually a steel rod having a hexagonally shaped socket which fits closely over the lug nut; sometimes in the shape of a cross, having several such sockets, one at the end of each arm, to accommodate nuts of different sizes. [1913 Webster +PJC]