Human Leg Muscle, the Longest in the Body

Puzzle 15 of Vlogging Pack

Question is: Human Leg Muscle, the Longest in the Body

and the answer is: SARTORIUS

Word Meaning:

SARTORIUS — (anatomy) A long, slender muscle that runs from the iliac crest along the anterior and medial aspects of the thigh to the proximal tibia, superficial to the quadriceps musculature; the longest muscle in the human body.

Definitions from Wiktionary.