Noun. 1. refrigerant-any substance used to provide cooling (as in a refrigerator). substance-a particular kind or species of matter with uniform properties; shigella is one of the most toxic substances known to man.cryogen-a liquid that boils at below -160 C and is used as a refrigerant.. A substance, such as air, ammonia, water, or carbon dioxide, used to provide cooling either as the working substance of a refrigerator or by direct absorption of heat. 2. Medicine An agent used to reduce fever.
usually offensive: a person affected with extreme mental retardation. 2. : a foolish or stupid person. â idiot adjective. See idiot defined for English-language learners.
A nerd is a person seen as overly intellectual, obsessive, or lacking social skills. Such a person may spend inordinate amounts of time on unpopular, little known, or non-mainstream activities, which are generally either highly technical, abstract, or relating to topics of fiction or fantasy, to the exclusion of more mainstream activities. Additionally, many so-called nerds are described as being shy, quirky, pedantic, and unattractive. Originally derogatory, the term nerd was a stereotype, bu