home Mikhail Wassmer diffuse dif⋅fuse [di-fyoos] –adjective 1. characterized by great length or discursiveness in speech or writing; wordy. 2. widely spread or scattered; dispersed. 3. Botany. widely or loosely spreading. 4. Optics. (of reflected light) scattered, as from a rough surface. d a b c d e f g h i j k l m n o p q r s t u v w x y z difficult doo-dz diffuse dilemma dinosaur disarray dog distance divided doily dirt dismantle dining-room