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

Duncan recently tore her ACL, and walked onto the stage in crutches. — Maddie Rhodes, USA Today, 28 Aug. 2026

Thompson, who is preparing for his 14th NBA season, is a different player at this point of his NBA career after tearing his ACL in 2019 and then rupturing his Achilles in 2020. — Anthony Chiang, Miami Herald, 27 Aug. 2026

That’s the big question for the Chiefs, as their three-time Super Bowl-winning quarterback is coming off a torn ACL that ended his 2025 season. — Nbc Sports, NBC news, 26 Aug. 2026

The Wave will look for more production from her down the stretch – especially with fellow Brazilian Dudinha still out with injuries to her ACL and meniscus. — Karan Lodha, New York Times, 26 Aug. 2026

Word History

First Known Use

1981, in the meaning defined above

Medical Definition

ACL

noun

ˌā-(ˌ)sē-ˈel 

: anterior cruciate ligament