Dugout

wiktionary

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From the verb phrase dug out.

etymonline

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dugout (n.)

also dug-out, 1722, "primitive type of canoe," consisting of a log with the interior hollowed out, American English, from past participle of dig (v.) + out (adv.). Baseball sense is recorded by 1914, from earlier meaning "rough shelter excavated in the side of a bluff or bank" (1855).