A large wasp, of the genus Vespa, having a brown-and-yellow-striped body and the ability to inflict a serious sting. / A person who pesters with petty but ceaseless attacks.

plural of hornet

(soccer) someone connected with Watford Football Club, as a fan, player, coach etc.

plural of Hornet

(military, informal) In the Vietnam War, a member of the US Air Force's 20th Special Operations Squadron, who used the Bell UH-1F variant of the "Huey" military helicopter.

(simile, informal) Extremely angry

plural of hornet fly

Any of the genus Asilus and allied genera of dipterous insects, of which there are numerous species; large and fierce flies which capture bees and other insects, often larger than themselves, and suck their blood.

(literally) A hornets' nest. / (figuratively) An unpleasant or controversial situation likely to be exacerbated by outside involvement.

cicada killer (not a true hornet)