deltoid

American  

[del-toid] / ˈdɛl tɔɪd /

noun

1. Anatomy. a large, triangular muscle covering the joint of the shoulder, the action of which raises the arm away from the side of the body.

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adjective

1. Anatomy. pertaining to or involving the deltoid.

2. Also in the shape of a Greek capital delta (Δ); triangular.

deltoid British  

/ ˈdɛltɔɪd /

noun

1. the thick muscle forming the rounded contour of the outer edge of the shoulder and acting to raise the arm

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adjective

1. shaped like a Greek capital delta, Δ; triangular

Other Word Forms

• subdeltoid adjective

Etymology

Origin of deltoid

1675–85; < Greek deltoeidḗs delta-shaped, equivalent to délt ( a ) delta + -oeidēs -oid

Example Sentences

All of the X-Men were strong, their muscles etched from deltoid to abdomen to quadriceps.

From Slate • Jul. 29, 2023

Servais had no update on reliever Andres Munoz, who is still working his way back from a deltoid strain in his right shoulder.

From Seattle Times • May 5, 2023

Mariners: LF Sam Haggerty is dealing with an isolated deltoid strain but is progressing, manager Scott Servais said.

From Washington Times • Aug. 24, 2022

The deltoid, the thick muscle that creates the rounded lines of the shoulder is the major abductor of the arm, but it also facilitates flexing and medial rotation, as well as extension and lateral rotation.

From Textbooks • Jun. 19, 2013

They would aim for the muscle that Tariq, in a professorial voice, called the deltoid.

From "A Thousand Splendid Suns" by Khaled Hosseini

Related Words

• trilateral