denoting a case (especially in Latin) of nouns and pronouns and words in grammatical agreement with them indicating an agent, instrument, or source, expressed by ‘by’, ‘with’, or ‘from’ in English

(of surgical treatment) involving ablation

all nine patients were treated by ablative surgery

relating to or subject to ablation through melting or evaporation

the spacecraft's ablative heat shield

a word in the ablative case