theory scientific theory https://en.wikipedia.org/wiki/Category:Scientific_theories https://en.wikipedia.org/wiki/Scientific_theory https://www.wikidata.org/wiki/Q3239681 An explanation of an aspect of the natural world that can be repeatedly tested and verified in accordance with the scientific method, using accepted protocols of observation, measurement, and evaluation of results. Where possible, theories are tested under controlled conditions in an experiment. scientific theories science