- to cause loss of focus of: The slightest movement will defocus the microscope.
- to interrupt or disturb (concentration, attention, etc.).
- to disturb the concentration or awareness of (someone).
- to lose or go out of focus.
- to lose concentration or awareness; become distracted.
- the result of defocusing, as a blurred photographic image.
Origin of defocus
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018