noun. a nitrogenous substance found in mucous secretions; a lubricant that protects body surfaces.
1. Noun, singular or mass If vesicles of mucin occur on the skin in the mouth or throat, your dog may snort and snore, and general anesthesia is risky. 2. Adjective “The eye increases tear production and mucin production as a mechanism to trap the irritants and remove them from the ocular surface,” she explains.