Mul'li·grubs noun [ Confer Prov. English mull to squeeze, pull about, mulling numb or dull.] 1. A griping of the intestines; colic. [ Slang] « Whose dog lies sick of the mulligrubs ?» Beau. & Fl. 2. Hence, sullenness; the sulks. [ Slang] Found on http://www.encyclo.co.uk/webster/M/113