AR-15

American  

[ey-ahr-fif-teen] / ˈeɪˈɑrˈfɪfˈtin /

Trademark.

1. a lightweight, gas-operated, magazine-fed rifle with a caliber of .223 inches, used for semiautomatic fire.

---

Etymology

Origin of AR-15

First recorded in 1960–65; shortening of ArmaLite Rifle, not of assault rifle ( def. ), as commonly thought

Example Sentences

He is co-author of the book "American Gun: The True Story of the AR-15."

From The Wall Street Journal • Apr. 16, 2026

Still, it was a place to gather reinforcements, so the convoy stopped under the town’s welcome arch and officers wielding AR-15 semiautomatic weapons found high ground to watch for threats.

From Los Angeles Times • Nov. 6, 2025

With armed guards with AR-15 rifles and pistols standing nearby, Mr Bloom introduced Ms Ferguson at a press conference as a "personal friend".

From BBC • Nov. 2, 2025

Guest: Cameron McWhirter, national affairs reporter for The Wall Street Journal covering mass shootings, violent protests, and natural disasters across the South and author of American Gun: the True Story of the AR-15.

From Slate • Sep. 25, 2024

The gun rack, set between two of the eight windows, held a Remington shotgun, a Colt AR-15 assault rifle, a tear-gas gun, and many rounds of ammunition.

From "Newjack: Guarding Sing Sing" by Ted Conover