Synonyms for Rotund (same or very similar meaning)
WordNet sense 1 (curving and somewhat round in shape rather than jagged):
roundedWordNet sense 2 ((of sounds) full and rich):
orotund, round, pear-shapedWordNet sense 3 ((of sound) having marked depth and body):
fullWordNet sense 4 (excessively fat):
corpulent, obese, weightyFrom the ODE community, based on WordNetadd/edit