1) in lacrosse, a chief who refuses to shoot overhand even when it would be more convenient to do so. a sidearm guy always shoots sidearm because he thinks it looks cool.

2) in life, anyone who insists on doing everything in a lazy or inappropriate manner. They wear hats cocked at stupid angles and leave trash all over the floor. this is derived from definition 1), as sidearm guys translate their sidearm ways into an entire lifestyle.
Hey sidearm guy how about shooting overhand once in a while? You might hit the cage. (P.S.... you're brute)

Hey sidearm guy how about putting your life back together.. it's in shambles right now.
by William Stickers III July 26, 2014
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