[in.de.clin.able] adj [ME, fr. MF, fr. LL indeclinabilis, fr. L in- + LL declinabilis capable of being inflected, fr. L declinare to inflect--more at decline] (14c): having no grammatical inflections
INDECLINABLE
Meaning of INDECLINABLE in English
Merriam-Webster English vocab. Английский словарь Merriam Webster. 2012