Syllable division and stress derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
thermally is an adverb meaning "by means of heat or with respect to thermal properties". It carries one recorded sense.
by means of heat or with respect to thermal properties
Definitions, synonyms and semantic relations for thermally come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.