Tumulate definitions Webster's 1828 Dictionary TU'MULATE, v.i. To swell. [Not in use.] Webster's 1913 Dictionary Tumulate Tu"mu*late, v. i. To swell. [Obs.] --Wilkins. Webster's 1913 Dictionary Tumulate Tu"mu*late, v. t. [L. tumulatus, p. p. of tumulare to tumulate. See Tumulus.] To cover, as a corpse, with a mound ...