deltoid muscle
nounUK /ˈdɛltɔɪd ˈmʌsəl/
US /ˈdɛltɔɪd ˈmʌsəl/
The deltoid muscle is the big muscle on your shoulder that helps you lift your arm.
He felt his deltoid muscle working when he raised his hand in class.
OTHER MEANINGS
2. A triangular-shaped muscle that covers the shoulder joint and allows the arm to move in many directions.
The doctor explained that the deltoid muscle controls lifting, pushing, and rotating the arm.
3. The muscle commonly used as an injection site for vaccines.
The nurse gave the shot in his deltoid muscle.
4. A muscle that can be strengthened with exercises like lateral raises.
Lifting small weights sideways helps build the deltoid muscle.