1. a suffix of nouns of quality, state, office, etc., many of which accompany adjectives ending in -acious or nouns or adjectives ending in -ate:fallacy; papacy; legacy; delicacy; piracy.

Origin of -acy

<Latin -ācia,-ātia (spelling interchangeably in Medieval Latin, reflecting the Rom merger of the forms); these are in turn complexes of -āc- and -āt--ate1 + -ia-y3. Cf. -cracy

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use -acy in a sentence

  • The village of Acy, high on the hill above the road to Venizel, was the richest hunting-ground.

  • I should like to devote a generous percentage to the use of the Confed'acy.

    The Debatable Land | Arthur Colton
  • At this moment a loud booming of cannon is heard in the direction of May-en-Multien, Acy.

    Beyond the Marne | Henriette Cuvru-Magot