Entry 2 senses Webster, 1913 Adiaphorous /(ăd`ĭ*ăf"ō̇*rŭs)/ · Ad·i·aph·o·rous · IPA 01 a. Indifferent or neutral. 1. Indifferent or neutral. 2. Incapable of doing either harm or good, as some medicines.(Med.)