Entry 1 sense Webster, 1913 keel over /kēl ōv'-ẽr/ · keel· o·ver · IPA /ˈkil ˈoʊvɚ/ 01 v. i. To drop down in a faint, or as if dead; to die. 1. To drop down in a faint, or as if dead; to die.[Colloq.]