knock boots

knock boots (with one)

euphemism To have sex (with one). My roommate in college used to hang a hat on the door handle outside our room if she was knocking boots with someone inside. I could tell he was more interested in knocking boots than in having any kind of serious relationship.
See also: boot, knock
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

knock boots

tv. to copulate. He said he wanted to knock boots with her.
See also: boot, knock
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.
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References in periodicals archive ?
If he wants to knock boots however, that is his business."
Monogamy and fidelity are put to the test, as self-proclaimed romantic Mitchell gets more than his share of offers to knock boots with a long list of B-boys.
Not only is he reunited with his love interest Ramada (Valeria Golino), but he also gets to knock boots with CIA glamour puss Brenda Bakke in nutty spoofs of No Way Out and Basic Instinct.