Men's or boys' baggy knee trousers, of a type particularly popular in the early 20th century.(noun)
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Use "knickerbockers" in a sentence
"The little boy in knickerbockers playing with a diabolo on page 103 is a perfect period piece."
"He was an extremely picturesque gardener, dressed in knickerbockers and leather gaiters, with a touch of red in his waistcoat, and a cardigan jacket and a cap on the side of his head."
"Across from Miss Hazel sat her brother in knickerbockers, his Alpine stock at his elbow and also his fan."