1. a muscle having two heads: such as

2. the large flexor muscle of the front of the upper arm
Despite a torn left biceps, Holmes used his jab, one of the best in heavyweight history, to win four of the first five rounds.
— Jack McCallum … they hold a dumbbell in each hand and do lateral raises with one arm while performing bicep curls with the other.
— Chloe Busch The biceps brachii, the rounded muscles that are easily identifiable, consists of a long and short head.
— Eric Sternlicht

3. the large flexor muscle of the back of the upper leg
Doctors had found a malignant tumor in her right biceps femoris muscle. … She had surgery at the end of February to have the growth and part of her hamstring muscle removed …
— Kelyn Soong

4. a large muscle at the front of the upper arm

5. a large muscle of the front of the upper arm

6. a muscle having two heads: as

7. the large flexor muscle of the front of the upper arm arising by its short head from the coracoid process and by its long head from the upper margin of the glenoid cavity and being inserted into the tuberosity of the radius

8. the large flexor muscle of the back of the upper leg that arises by its long head from the tuberosity of the ischium and by its short head from the shaft of the femur, that is inserted into the head of the fibula, its tendon forming the outer hamstring, and that flexes the leg on the thigh and extends the thigh on the trunk