knee
n. countablen. the middle part of your leg where it bends. You use it to sit down, walk, or run.
n. the joint between the thigh and the lower leg in humans. It is a complex hinge joint that allows for flexion and extension.
He fell down and hurt his knee while playing football.
The doctor asked the patient to bend her knee to check for any signs of ligament damage.
The athlete underwent surgery to repair a torn ligament in his left knee, a common injury that requires months of physical therapy to ensure a full recovery.
From Middle English kne, from Old English cnēow, from Proto-West Germanic kneu, from Proto-Germanic knewą, from Proto-Indo-European ǵnéw-o-m, a thematic derivative of ǵónu. See also West Frisian knibbel, Low German Knee, Knie, Dutch knie, German Knie, Danish knæ, Norwegian kne, Swedish knä; also Hittite 𒄀𒉡 (genu), Latin genū, Tocharian A kanweṃ (dual), Tocharian B kenī, Ancient Greek γόνυ (gónu, “knee”), γωνία (gōnía, “corner, angle”), Welsh glin (“knee”), Old Armenian ծունր (cunr), Avestan 𐬲𐬥𐬎𐬨 (žnum), Sanskrit जानु (jā́nu). The obsolete plural kneen is from Middle English kneen, knen, kneon, kneuwene.
Commonly used with verbs like 'bend', 'flex', or 'scrape'.