.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

He has maintained he did not pull the trigger of the Colt .45 pistol and only drew back its hammer.

From BBC • Feb. 20, 2024

Other children don’t find “$50,000 in Krugerrands and a .45 automatic when they’re hunting for Easter eggs.”

From Los Angeles Times • Feb. 7, 2024

Following Nick, the old man watched with interest as the storekeeper, after searching among the ammunition for a moment, selected a box of .45 shells, which he slapped into Amarante’s hands.

From "The Milagro Beanfield War" by John Nichols