What are the best answers for “an act that changes the form or character or substance of something”?

transmutation, transubstantiation.

How many letters does the top answer for “an act that changes the form or character or substance of something” have?

The most common answer is transmutation (13 letters).

2 answers found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

transmutation 13 letters wn-def

an act that changes the form or character or substance of something

transubstantiation 18 letters wn-def

an act that changes the form or character or substance of something