Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
pentamerous is an adjective meaning "divided into five parts; specifically, having each floral whorl consist of five (or a multiple of five) members". It carries one recorded sense.
divided into five parts; specifically, having each floral whorl consist of five (or a multiple of five) members
“pentamerous flowers”
botany
Definitions, synonyms and semantic relations for pentamerous come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.