Noun[edit] malapropism â(plural malapropisms) (uncountable) The blundering use of an absurdly inappropriate word or expression in place of a similar-sounding one.
Definition of positron. : a positively charged particle having the same mass and magnitude of charge as the electron and constituting the antiparticle of the electron âcalled also antielectron.
Positron emission tomography (PET) scan A computerized diagnostic technique that uses radioactive substances to examine structures of the body. When used to assess the brain, it produces a three-dimensional image that reflects the metabolic and chemical activity of the brain.