ACL

noun

ˌā-(ˌ)sē-ˈel 

plural ACLs

: a cruciate ligament of each knee that attaches the front of the tibia with the back of the femur and functions especially to prevent hyperextension of the knee and is subject to injury especially by tearing

The athlete tore their ACL during a practice game.

called also anterior cruciate ligament

Examples of ACL in a Sentence

Recent Examples on the Web

Mahomes’ rapid recovery from last year’s ACL/LCL catastrophe is great news for Kansas City fans and the NFL’s TV/streaming partners, as he and the Chiefs are slated to pop up in as many as 12 national windows before the playoffs arrive. — Anthony Crupi, Sportico.com, 9 Oct. 2026

The hotel plays up its proximity to ACL Live, with framed photographs of the show and an Austin City Limits coffee table book of images captured by the same photographer. — Condé Nast, Condé Nast Traveler, 8 Oct. 2026

Former Brooklyn Net Kyrie Irving returns Friday in Macao, 19 months after his ACL tear. — Kristian Winfield, New York Daily News, 8 Oct. 2026

Watkins returns after missing last season with a torn ACL and will join the country’s top recruiting class to try to help USC return to the nation’s elite and extend the rivals’ dominance over their new league. — Luke Decock, Los Angeles Times, 7 Oct. 2026

Word History

First Known Use

1981, in the meaning defined above

Medical Definition

ACL

noun

ˌā-(ˌ)sē-ˈel 

: anterior cruciate ligament