Someone who tends to exaggerate their accomplishments to impress others. There may be a kernel of truth in their claims -- making it difficult to call 'bullshit' on them, not to mention the social risk involved in doing so -- but their exaggeration extends far beyond what might be considered remotely truthful.
More often than not, a dorky male with no real accomplishments to their name.
Jill: I've taken up learning the violin as a hobby.
Jack the embellisher: Oh, well I used to be a concert violinist.
Jack's friend: Lay it off dude, you learnt the violin for 8 weeks in primary school, and gave it up because you found it too hard.
Nickname given to bales of marijuana thrown overboard or out of airplanes. Origin is reportedly from members of the US Coast Guard in the area of Southern Florida.
"Base we've got some square groupers floating outside of Miami harbor."