TROCHAL DISC Meaning of TROCHAL DISC in English ■ noun Zoology each of two projections below the neck of the femur (thigh bone) to which muscles are attached.OriginC19: trochal from Gk trokhos 'wheel' + -al . Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004