Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
leastwise is an adverb meaning "if nothing else (`leastwise' is informal and `leastways' is colloquial)". It carries one recorded sense.
if nothing else (`leastwise' is informal and `leastways' is colloquial)
“at least he survived”
“they felt--at any rate Jim felt--relieved though still wary”
“the influence of economists--or at any rate of economics--is far-reaching”
colloquialism
Definitions, synonyms and semantic relations for leastwise come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.