Comparative form of 'fierce'; more fierce, intense, ferocious, or aggressive than another.
From 'fierce' (Old French 'fiers') with the comparative suffix -er (from Old English -ra/-or). For one-syllable and some two-syllable adjectives, English adds -er instead of using 'more.'
English has two systems for comparing adjectives—short words add -er/-est (fiercer, fiercest) while longer words use more/most (beautiful, more beautiful). This split evolved naturally as the language developed over centuries.
Complete word intelligence in one call. Free tier — 50 lookups/day.