1

deltoid

noun del·toid \ ˈdel-ˌtȯid \

Definition of deltoid

: a large triangular muscle that covers the shoulder joint and serves to raise the arm laterally

Recent Examples of deltoid from the Web

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Did You Know?

The fourth letter of the Greek alphabet is delta, and a capital delta is triangle-shaped. In English, delta commonly means the sand deposits that form a huge triangle at the mouth of certain large rivers. Deltoid as an adjective means "having a triangular shape", and botanists often use the word to describe the shape of certain leaves. The triangular, swept-back wings seen on jet fighter aircraft are called delta wings. Your deltoid muscles—not far from your rhomboids—form a cap on your shoulders, and some gym trainers even treat shoulder and deltoid as synonyms. Can you guess the general shape of deltoids when seen from the side?

Origin and Etymology of deltoid

New Latin deltoides, from Greek deltoeidēs shaped like a delta, from delta


2

deltoid

adjective

Definition of deltoid

1 : having a triangular shape
  • a deltoid leaf
— see leaf illustration
2 : relating to, associated with, or supplying the deltoid

First Known Use of deltoid

circa 1753


DELTOID Defined for English Language Learners

deltoid

noun

Definition of deltoid for English Language Learners

  • : a large muscle of the shoulder


Medical Dictionary

1

deltoid

noun del·toid \ ˈdel-ˌtȯid \

medical Definition of deltoid

: a large triangular muscle that covers the shoulder joint, serves to raise the arm laterally, arises from the upper anterior part of the outer third of the clavicle and from the acromion and spine of the scapula, and is inserted into the outer side of the middle of the shaft of the humerus called also deltoid muscle; see deltoid tuberosity

Illustration of deltoid


2

deltoid

adjective

medical Definition of deltoid

: relating to, associated with, or supplying the deltoid
  • the deltoid branch of the thoracoacromial artery

Learn More about deltoid


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