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-atory

American  

  1. a combination of -ate and -ory or -ory, used infrequently as an independent suffix with the same senses as -ory and -ory: affirmatory; observatory .

-atory British  

suffix

  1. of, relating to, characterized by, or serving to

    circulatory

    exploratory

    migratory

    explanatory
"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 -atory

< Latin -ātōrius, -a, -um, originally the termination of adjectives formed with -tōrius ( -tory 1, -tory 2 ) and verbs whose stems ended in -ā-; reanalyzed in English in the same way as -ator

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.