-atory

a combination of -ate¹ and -ory¹ or -ory², used infrequently as an independent suffix with the same senses as -ory¹ and -ory²: affirmatory; observatory.

Origin of -atory

< Latin -ātōrius, -a, -um, orig. the termination of adjectives formed with -tōrius (see -tory¹, -tory²) and verbs whose stems ended in -ā-; reanalyzed in English in the same way as -ator

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British Dictionary definitions for -atory

-atory

suffix forming adjectives

of, relating to, characterized by, or serving tocirculatory; exploratory; migratory; explanatory

Word Origin for -atory

from Latin -ātōrius; see -ate 1, -ory ²

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