The Collaborative International Dictionary of English v.0.48:

Pup \Pup\, v. i. [imp. & p. p. Pupped; p. pr. & vb. n.
   Pupping.]
   To bring forth whelps or young, as the female of the canine
   species.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Pup \Pup\, n. [See Puppy.] (Zool.)
   (a) A young dog; a puppy.
   (b) a young seal.
       [1913 Webster]

WordNet (r) 3.0 (2006):

pup
    n 1: young of any of various canines such as a dog or wolf [syn:
         pup, whelp]
    2: an inexperienced young person [syn: puppy, pup]
    v 1: birth; "the dog whelped" [syn: whelp, pup]

Moby Thesaurus II by Grady Ward, 1.0:

107 Moby Thesaurus words for "pup":
   Seeing Eye dog, bandog, be confined, bear, bear a child,
   bear young, birdling, bitch, boldface, bowwow, boy, brazenface,
   bub, bubba, buck, bud, buddy, calf, calve, canine, cast, catling,
   chick, chickling, chicky, chutzpanik, colt, cub, dog, dogie, drop,
   duckling, fancy dog, farrow, fawn, fellow, fledgling, foal, fryer,
   give birth, gosling, guide dog, gyp, have, have a baby, have young,
   hobbledehoy, hussy, kennel, kid, kit, kitten, labor, lad, laddie,
   lamb, lambkin, lap dog, lie in, litter, malapert, manchild, master,
   minx, muchacho, nest, nestling, pack of dogs, piglet, pigling,
   polliwog, pooch, pullet, puppy, saucebox, schoolboy, sheep dog,
   shoat, show dog, sled dog, slut, smart aleck, smart-ass, smarty,
   smarty-pants, sonny, sonny boy, sprat, squirt, squit, swaggerer,
   tadpole, throw, toy dog, travail, upstart, watchdog, weaner, whelp,
   whippersnapper, wise guy, wise-ass, working dog, yean, yeanling,
   young man, youth



V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

PUP
       PARC Universal packet Protocol (PARC)


V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

PUP
       Product UPgrade (MS)