noun ·Rare ·Advanced level

Definitions

Noun

1. 1
   invalidity; the state of being invalid uncountable

   "the invalidness of reasoning"

2. 2
   illogicality as a consequence of having a conclusion that does not follow from the premisses wordnet

Synonyms

All synonyms

invalidityinvalidity

Antonyms

All antonyms

legitimacy

Etymology

From invalid + -ness.

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.