Heavier is the comparative form of the adjective heavy, so it is called a comparative adjective.
The boy is heavier than the girl.
heavier, heaviest
heavier, heaviest
That is not a question, but a statement. Statements in English are suffixed by period (.), not question mark (?).heavy - heavier - heaviest
It can be, but only as the superlative form of "heavy" used as an adverb. Heavy, heavier, and heaviest are all normally adjectives. But in some rare uses, both heavy and its comparatives can be used as adverbs. e.g. The snow is falling heavier than before. (more heavily) Time hangs heaviest on their shoulders. (most heavily)
Comparative: Noisier Superlative: Noisiest
heaviest
heaviest, heavier
heavier, heaviest
heavier, heaviest
Heavier is the comparative adjective for heavy. The superlative is heaviest.
Comparative: heavy, heavier Superlative: heavy, heavier, heaviest
heavier, heaviest
heavier, heaviest
heavier, heaviest
heaviest, heavier
heavier, heaviest
heavier, heaviest