.45

¹ American  

noun

plural

.45s, .45's

1. a pistol, revolver, or cartridge of .45-caliber, or having a diameter of .45 inch.

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45 ² American  

[fawr-tee fahyv] / ˈfɔr ti ˈfaɪv /

noun

plural

45s, 45's

1. a seven-inch phonograph record played at 45 r.p.m., especially a popular-music single.

   She’s in the market for a phonograph so she can play her grandfather’s mint collection of 45s from the 1960s.

2. an identifier of or nickname for Donald Trump, the 45th U.S. president, alternately used with disparaging intent by opponents and with affection by supporters.

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Etymology

Origin of 45

First recorded in 1945–50

Example Sentences

Spivey's .45 caliber, like most firearms, ejects casingsbehind and to the right.

From The Wall Street Journal • Dec. 21, 2025

Hours later he would come ashore with a .45 pistol, pencils, and a sketchbook.

From Slate • Jun. 6, 2025

The 66-year-old actor was practising firing a Colt .45 pistol before filming a scene for Rust, a forthcoming Western filmed near Santa Fe, New Mexico, in October 2021.

From BBC • Apr. 9, 2024

Gutierrez has acknowledged loading Baldwin’s Colt .45 revolver on that sunny October day with what she thought were inert “dummy” rounds.

From Los Angeles Times • Feb. 22, 2024

With his long raincoat with the popped-up collar and the .45 in his wide leather belt, he looked like an old-timey gunslinger.

From "The Marrow Thieves" by Cherie Dimaline