pooch /puːt͡ʃ/noun 5verb 1forms 3phrases 2 noun5 •A dog of mixed breed; a mongrel. •(informal) A dog.She’s just been playing with the pooch ever since they got in the field. •(informal) A bulge, an enlarged part.There's a pooch in the plastic where it got too hot. •(informal) A distended or swelled condition.Her left sleeve has more pooch at the shoulder than the right. •(informal) The lower belly region; often in reference to the stubborn fat stored in the abdominal area. verb1 •(informal) To distend, to swell or extend beyond normal limits; usually used with out.Inflate that tire too much and the tube may pooch out of the cut in the sidewall. formspooched · pooching · pooches Phrases with pooch pooch outTo form a bulge or lump. screw the poochto make a large mistake, to fail in dramatic and ignominious fashion.