(adj) having no justifying cause or reason, Syn. reasonless, Example:a senseless, causeless murder; a causeless war that never had an aim; an apparently arbitrary and reasonless change
(adj) having no cause or apparent cause, Syn. fortuitous, uncaused, Example:a causeless miracle; fortuitous encounters--strange accidents of fortune; we cannot regard artistic invention as...uncaused and unrelated to the times