Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
fearfulness is a noun meaning "an emotion experienced in anticipation of some specific pain or danger (usually accompanied by a desire to flee or fight)". It carries 2 recorded senses.
an emotion experienced in anticipation of some specific pain or danger (usually accompanied by a desire to flee or fight)
the trait of being afraid
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for fearfulness come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.