One who talks the talk, but could never walk the walk.
One who talks shit and doesn't back it up, but rather ends up eating their shit in return.
A fuckin 'tard.
Bob: "oh yeah, well..(breaks Bill's face in half)...who's the fuckin' pussy now you fuckin Jabroni?!"
Damn Jabroni's, I'm always breaking my foot off in their asses!