1) Become laryngitic 2) Become raspy 3) Get raspier 4) Get rough 5) Lose mellifluence 6) Make raspy 7) To make or become hoarse Found on https://www.crosswordclues.com/clue/hoarsen
Hoars'en transitive verb [ imperfect & past participle Hoarsened ; present participle & verbal noun Hoarsening .] To make hoarse. « I shall be obliged to hoarsen my voice.» Richardson. Found on http://www.encyclo.co.uk/webster/H/50