Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
noninterchangeable is an adjective meaning "such that the terms of an expression cannot be interchanged without changing the meaning". It carries one recorded sense.
such that the terms of an expression cannot be interchanged without changing the meaning
“the arguments of the symmetric relation, `is the father of', are noninterchangeable”
mathematics · logic
Definitions, synonyms and semantic relations for noninterchangeable come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. .