2.nounA type of men's headwear, made of cloth with a plaid pattern, having two projecting brims (one at the front and one at the back) and earflaps which can be folded up and tied at the top.
"Two famous fictional characters who wore deerstalker hats were Sherlock Holmes and Holden Caulfield in J. D. Salinger's Catcher in the Rye."