I have an envelope/continental!
Bifold: Any two-sectioned wallet that folds in half to close; usually fits in a pants pocket; sometimes referred to as a "hipster"
Checkbook: A wallet that is sized to hold a standard book of checks and unfolded currency
Clutch: A purse-like wallet that can be carried in one hand on its own
Coin: A sturdy wallet with a secure kiss-lock, zipper, or snap closure, designed to hold coins
Envelope/Continental: A long, slender rectangular wallet that has size and proportions similar to those of a business envelope
ID wallet: A very small, thin wallet designed to hold an ID, a few credit cards, limited cash and perhaps a key; convenient for those who do not want to carry anything bulky
Opera wallet: A flat, hard-cased wallet that snaps shut
Trifold: Any three-sectioned wallet that folds twice to close and fits in a pants pocket
Wristlet: A wallet that features a short strap that allows the wallet to be carried in the hand or around the wrist