different between nubby vs tubby

English

nub +? -y. Compare knobby.

nubby (comparative nubbier, superlative nubbiest)

Knobbly; covered with small knobs.
- 2007, Marie Clayton, The Ultimate A to Z Companion to 1,001 Needlecraft Terms:
  noil A type of silk, sometimes incorrectly called raw silk, with a nubby feel and a low sheen.
Nub-like, resembling a small bump or protrusion; stubby.
- 2010, John Leigh Walters, A Very Capable Life: The Autobiography of Zarah Petri, page 170:
  Now we are sitting in a circle and each is given a stenographer's pad, the kind with the spring spine, and a nubby pencil, a pencil of quarter size so it can't be used as a weapon [...]

From tub +? -y. False cognate with chubby, even though they are often interchangeable.

tubby (comparative tubbier, superlative tubbiest)

stout, rotund
Resembling a tub; sounding dull and without resonance or freedom of sound.
a tubby violin

tubby (plural tubbies)

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