Culling is the process of removing breeding animals from a group based on specific criteria. This is done either to reinforce certain desirable characteristics or to remove certain undesirable characteristics from the group.For livestock and wildlife alike, culling usually implies the killing of the removed animals.iktionary (0.00 / 0 votes) Rate this definition: culling (Noun). The act of culling; the process of selecting for acceptance or removal. culling (Noun). Anything separated or selected from a mass.