Pugnacious

pug⋅na⋅cious   [puhg-ney-shuhs]
–adjective
1. inclined to quarrel or fight readily; quarrelsome; belligerent; combative.
2. tough and callous by virtue of experience

Related forms:
pug⋅na⋅cious⋅ly, adverb
pug⋅nac⋅i⋅ty  [puhg-nas-i-tee]
pug⋅na⋅cious⋅ness, noun

example:
He had a strong, pugnacious face.

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