1. a device that spreads or scatters light, air, or other substances evenly
2. a device that releases fragrance or essential oils into the air
3. an attachment for a hair dryer that spreads airflow to reduce frizz

Examples

• The photographer used a light diffuser to create softer shadows.
• She placed an essential oil diffuser in her bedroom for relaxation.
• The air conditioning system has diffusers in the ceiling to distribute cool air evenly.
• I always use a diffuser attachment when blow-drying my curly hair.
• The studio’s lighting setup included several diffusers to eliminate harsh glare.
• The lavender diffuser filled the room with a calming scent.
• Without a diffuser, the flash created unflattering shadows in the portrait.