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pl.n. Vulgar Slang
1. The testicles.
a. Boldness or courage.
b. Presumptuousness; nerve.
[Spanish, pl. of cojón, testicle, from Vulgar Latin *cōleō*cōleōn-, from Latin cōleī, testicles, perhaps a colloquial variant of *culleī and akin to culleus, leather sack, probably a borrowing from an unknown Indo-European language of the Mediterranean and akin to Greek koluthron, ripe fig (perhaps originally "sacklike thing"), koluthroi, testicles, and koleon, sheath; see coleopteran.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
1. (Anatomy) testicles
2. manly courage
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014