say it: BIT-ur-nuhs
bitterness is a noun meaning "a feeling of deep and bitter anger and ill-will". It carries 4 recorded senses.
a feeling of deep and bitter anger and ill-will
a rough and bitter manner
the property of having a harsh unpleasant taste
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 bitterness come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.