from The American Heritage® Dictionary of the English Language, 4th Edition
- adj. Smart in appearance or dress; stylish.
- transitive v. To make attractive, stylish, or up-to-date: spiffying up my wardrobe.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. Dapper; fine or neat, especially in style of clothing or other appearance.
from The Century Dictionary and Cyclopedia
- Spruce; well-dressed.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- adj. marked by up-to-dateness in dress and manners
Possibly from dialectal spiff, dandified.(American Heritage® Dictionary of the English Language, Fourth Edition)
spiff + -y (Wiktionary)