As nouns the difference between ruffian and brawler
is that
ruffian is a scoundrel, rascal, or unprincipled, deceitful, brutal and unreliable person while
brawler is one who brawls, engages in noisy, unseemly fights.
As a verb ruffian
is to play the ruffian; to rage; to raise tumult.
As an adjective ruffian
is brutal; cruel; savagely boisterous; murderous.