It's already a three-letter name. Can't simplify that much more.
Famous people named Roy:
Singers Roy Orbison and Roy Acuff; actors Roy Rogers and Roy "RJ" Mitte; co-founder of the Walt Disney Company, Roy Disney.
ROY G. BIV is the popular acronym for the orders of the color in a rainbow: red, orange, yellow, green, blue, indigo, and violet.