Z movie
Z movies are low-budget films that have qualities lower than B movies.
History and terminology
The term Z movie (or grade-Z movie) arose in the mid-1960s as an informal description of certain unequivocally non-A films. It was soon adopted to characterize low-budget pictures with quality standards well below those of most B movies and even so-called C movies. While B movies may have mediocre scripts and actors who are relatively unknown or past their prime, they are for the most part competently lit, shot, and edited.