Motion picture? (4)
'motion picture' is the definition.
(I know that motion picture can be written as movie)
This is the entire clue.
(Other definitions for movie that I've seen before include "one screened" , "Cinema film (mainly US)" , "Flick" , "picture" , "provide entertainment" .)
(Other definitions for blur that I've seen before include "Hazy or indistinct image" , "Obscure; smudge" , "murky spot" , "Confused impression" , "Haze - obscure" .)