(physics) Initialism of grand unification theory or grand unified theory.

The alimentary canal, especially the intestine. / (informal) The abdomen of a person, especially one that is enlarged

Made of gut. / Instinctive.

(transitive) To eviscerate. / (transitive) To remove or destroy the most important parts of.

A surname from German.

Third-person singular simple present indicative form of gut

The entrails or contents of the abdomen. / (by extension, informal) Courage; determination. / (informal) Content, substance. / (informal) The essential, core parts. / (informal) One's innermost feelings.

(Australia, informal) To eat greedily. / (informal) To show determination or courage (especially in the combination guts out).

plural of gut

(Britain) Disheartening, crushing.