1 definition by @lligator

An internet chat abbreviation for "retarded giggles"; applicable when reading a message and in stead of 'laughing out loud', you let out a short, obnoxious, manatee-sounding laugh. An 'RG' can also be considered such if the person tilts there head back in laughter, appearing to unhinge their jaw from hysteria.
Instant Message conversation:

Adam:...although now i just remembered we were c-sectioned...seasectioned...seesectioned...ceesectioned...idk how to spell it so i'm giving multiple ways

Alex: RG... i just choked on skittle

Adam: your giggles are always retarded
by @lligator February 10, 2009
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