dyspeptic \dis-pep-tik\ (adjective) - Suffering from indigestion or morose or disgruntled as if suffering from an upset stomach.
"No one in the office was certain if the new supervisor's dyspeptic attitude was indicative of an actual stomach problem or merely an affectation to keep those in his department off balance."
Today's word derives from a mixture of bodily functions and gastronomy: Greek dys- "bad, wrong" + pepsis "digestion." Digestion to our forebears was just another form of cooking, since "pepsis" derives from pepein "to cook, ripen" (cf. Russian pishchevarenie "digestion," literally "food-cooking"). The same root, *pekw-, gave Russian pech' "bake, roast" and Sanskrit pakva "ripe." In the dys- family we find dyscrasia "abnormal blood condition" from dys- + krasis "mixing" and dyslexia "impaired reading ability" from dys- + lexis "speech."