Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
sombreness is a noun meaning "a state of partial or total darkness". It carries 3 recorded senses.
a state of partial or total darkness
“he struck a match to dispel the gloom”
a feeling of melancholy apprehension
a manner that is serious and solemn
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 sombreness come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.