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ruga

[roo-guh]
noun, plural ru·gae [roo-jee, -gee] /ˈru dʒi, -gi/.
  1. Usually rugae. Biology, Anatomy. a wrinkle, fold, or ridge.

Origin of ruga

First recorded in 1765–75, ruga is from the Latin word rūga
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for ruga

ruga

noun plural -gae (-dʒiː)
  1. (usually plural) anatomy a fold, wrinkle, or crease

Word Origin for ruga

C18: Latin
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
ruga in Medicine

ruga

[rōō′gə]
n. pl. ru•gae (-gē′, -gī′)
  1. A fold, crease, or wrinkle, as in the lining of the stomach. Often used in the plural.
Related formsru′gate′ (-gāt′) adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.