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

Mykel Williams, a 2024 first-round draft pick, is recovering from an ACL tear last November but is expected to return to practice next week after beginning the season on the physically unable to perform list. — Chris Biderman, Sacbee.com, 25 Sep. 2026

Bell said doctors told him that those symptoms are not uncommon for athletes who have returned from ACL injuries. — Barry Jackson, Miami Herald, 24 Sep. 2026

The only good news in this entire scenario is that Dart did not sustain any damage to his ACL. — Armando Salguero Outkick, FOXNews.com, 23 Sep. 2026

After being hurt, Mahomes didn’t wait for the swelling in his knee to go down before having the anterior cruciate ligament (ACL) and lateral collateral ligament (LCL) in his left knee repaired. — Pete Grathoff, Kansas City Star, 23 Sep. 2026

Word History

First Known Use

1981, in the meaning defined above

Medical Definition

ACL

noun

ˌā-(ˌ)sē-ˈel 

: anterior cruciate ligament