Flyhands McGregors was an underground Jazz artist in 1930's New Orleans. He also dabbled in glove making, cigar rolling, and general oven mitt tomfoolery before becoming a musician. Now, the word is used to describe an unusually hip, or trendy person. It can also be used to describe large dark frame sunglasses.
Look how nice he dresses, he's such a Flyhands McGregors.

Man, Eric Estrada has some nice Flyhands McGregors glasses on.
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