life history noun3 •An investigation into the details and activities of a person over the course of their lifetime; one’s background.His life history shows that he frequently moves from town to town, moving from one job to the next. •Information concerning a person’s diseases and medical disorders suffered during his or her lifetime; especially useful if the disorders are genetic. •The set of stages that an organism, or a species, experiences over its lifetime, from conception to death. formslife histories