Definition of oral

• of or relating to or affecting or for use in the mouth; "oral hygiene"; "an oral thermometer"; "an oral vaccine"
• of or involving the mouth or mouth region or the surface on which the mouth is located; "the oral cavity"; "the oral mucous membrane"; "the oral surface of a starfish"
• a stage in psychosexual development when the childs interest is concentrated in the mouth; fixation at this stage is said to result in dependence, selfishness, and aggression