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Also, mad as hell or hops or a wet hen. Very angry, enraged as in Mary was mad as a hornet when her purse was stolen, or Upset? Dan was mad as hell, or The teacher was mad as a wet hen. The use of mad for "angry" dates from about 1300, but these similes are of much more recent vintage (1800s, early 1900s). The allusions to a hornet, which can launch a fierce attack, and hell, with its furious fires, are more obvious than the other variants. Mad as hops was first recorded in 1884 and is thought to have been the writer's version of HOPPING MAD; mad as a wet hen, first recorded in 1823, is puzzling, since hens don't really mind water.
American Heritage Idioms
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Phrase(s): *mad as a hornet [and] *mad as a wet hen; *mad as hell
very angry. (*Also: as ~. Use hell with caution.) • You make me so angry. I’m as mad as a hornet. • What you said made Mary mad as a wet hen. • Those terrorists make me mad as hell.
McGrawhill's American Idioms And Phrasal Verbs