mesomorphic

from WordNet (r) 3.0 (2006)

mesomorphic
    adj 1: having a robust muscular body-build characterized by
           predominance of structures (bone and muscle and
           connective tissue) developed from the embryonic
           mesodermal layer [syn: {mesomorphic}, {muscular}] [ant:
           {ectomorphic}, {endomorphic}, {pyknic}]

from The Collaborative International Dictionary of English v.0.48

bull-necked \bull"-necked`\, a.
   Having a short, thick and muscular neck like that of a bull.
   --Sir W. Scott. [Narrower terms: {mesomorphic}]
   [1913 Webster + WordNet 1.5]

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