[in-di-klahy-nuh-buh l]
adjective Grammar.
  1. not capable of being declined; having no inflected forms: used especially of a word belonging to a form class most of whose members are declined, as the Latin adjective decem, “ten.”

Origin of indeclinable

1400–50; late Middle English < Latin indēclīnābilis unchangeable, inflexible. See in-3, declinable
Related formsin·de·clin·a·ble·ness, nounin·de·clin·a·bly, adverb Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for indeclinable

Historical Examples of indeclinable

  • Of these, the first five are declinable; the other four are indeclinable.

  • The genitives his (his, its), hiere (her), hiera (their) are used as indeclinable possessives.

  • Mīlle is regularly an adjective in the Singular, and indeclinable.

    New Latin Grammar

    Charles E. Bennett

  • The indeclinable, remain as simple adjuncts to the verbs, and the latter put on the negative form.

    The Indian in his Wigwam

    Henry R. Schoolcraft

British Dictionary definitions for indeclinable


  1. (of a noun or pronoun) having only one form; not declined for case or number
Derived Formsindeclinableness, nounindeclinably, adverb
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

Word Origin and History for indeclinable

late 14c., originally in grammar, from French indéclinable, from Latin indeclinabilis, from indeclinatus "unchanged, constant," from in- "not, opposite of" (see in- (1)) + declinatus, from declinare (see decline (v.)). Related: Indeclinably.

Online Etymology Dictionary, © 2010 Douglas Harper