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n. The deltoid muscles.

noun-plural. The deltoid muscles; -- a contraction used by body-building and health enthusiasts. Used similarly to abs and pecs. See deltoid muscle.

"He could tell; the ridges that defined the tectonics of his delts were a little less precise, the knobs that represented his abs a little less jagged, the bulge of his veins a little less prominent."

abs    pecs   

delta