pooch

Etymology 1

Of uncertain origin. One (unsubstantiated) conjecture is that the word comes from Putzi, a common German name given to lapdogs. The name Putzi is possibly formed from German Putz + -i, influenced by German putzig (“funny, cute, small”, adjective).

noun

1. (slang) A dog.
   My thoughts are disturbed by a man and pooch trying to get off the front of the train. Despite hitting the door button, they refused to open. November 2 2022, Paul Bigland, “New trains, old trains, and splendid scenery”, in RAIL, number 969, page 58
2. A dog of mixed breed; a mongrel.

Etymology 2

Probably related to pouch.

noun

1. (countable) A bulge, an enlarged part.
   There's a pooch in the plastic where it got too hot.
2. A distended or swelled condition.
   Her left sleeve has more pooch at the shoulder than the right.

verb

1. 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.
   There were rustling sounds from the tent and the sides pooched out as if they were trying to stand up. 1969, Maya Angelou, chapter 21, in I Know Why the Caged Bird Sings, New York: Bantam, published 1971, page 124