Coexist \Co`ex*ist\, v. i. [imp. & p. p. {Coexisted}; p. pr. & vb. n. {Coexisting}.] To exist at the same time; -- sometimes followed by with. Of substances no one has any clear idea, farther than of certain simple ideas coexisting together. --Locke. So much purity and integrity . . . coexisting with so much decay and so many infirmities. --Warburton.