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del·toid

(dĕltoid′)

1. A thick triangular muscle covering the shoulder joint, used to raise the arm from the side.

2. See kite.

adj.

a. Triangular.

b. Having the shape of a geometric kite.

2. Of or relating to the deltoid.

[New Latin deltoīdēs, from Greek deltoeidēs, triangular : delta, delta; see DELTA + -oeidēs, -oid.]

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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