Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
precautional is an adjective meaning "taken in advance to protect against possible danger or failure". It carries one recorded sense.
taken in advance to protect against possible danger or failure
“gave precautionary advice”
“I would take precautionary steps to keep him away”
Definitions, synonyms and semantic relations for precautional come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.