strain

³strain

noun

Definition of STRAIN

: an act of straining or the condition of being strained: as a : excessive physical or mental tension; also : a force, influence, or factor causing such tension b : bodily injury from excessive tension, effort, or use <heart strain>; especially : one resulting from a wrench or twist and involving undue stretching of muscles or ligaments <back strain>—compare sprain c : deformation of a material body under the action of applied forces