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ides

1 American  
[ahydz] / aɪdz /

noun

(used with a singular or plural verb)

  1. (in the ancient Roman calendar) the fifteenth day of March, May, July, or October, and the thirteenth day of the other months.

-ides 2 American  

  1. a Greek plural suffix appearing in scientific names.

    cantharides.
ides British  
/ aɪdz /

noun

  1. (functioning as singular) (in the Roman calendar) the 15th day in March, May, July, and October and the 13th day of each other month See also calends nones

"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

Etymology

Origin of ides1

1300–50; Middle English < Old French < Latin īdūs (feminine plural); replacing Middle English idus < Latin

Origin of -ides2

< Greek, plural of -is, suffix of source or origin. See -id 1

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.