Answer: tubbiest

AnswerCrossword Clue
TUBBIESTDecidely roly-poly, to the max
TUBBIESTLeast resonant
TUBBIESTMost rotund
tubbiest(of a person) Short and rather fat
tubbiestTUBBY, round like a tub
tubbiest(of a sound) Lacking resonance; dull