blinkies: coupons found in the store isle in blinking coupon dispensers (usually from SmartSource)
BOGO or B1G1: buy one, get one free
Catalina: a coupon that prints at the cash register from a separate machine. It has a red stripe along the top and bottom and is frequently good for $x off your next order.
CRT: cash register tape
CVS: a chain pharmacy which tends to have really great deals. There are CVS pharmacies in most states and is one of the largest pharmacies in the United States.
double coupon: when a store gives double credit for a coupon, usually up to a certain limit, such as $1.00. For instance, if you buy an item with a $.75 coupon and the store doubles up to $1.00, you would get $1.00 off your total. If in the same store you had a $.45 coupon, you would get $.90 off your order.
ECB: easy care bucks (CVS), may be earned by purchasing specific advertised products and can be used as "CVS cash"
ESC: easy saver coupon (Walgreens), part of the monthly savings booklet; these are store coupons and may therefore be used with manufacturer's coupons
ESR: easy saver rebate (Walgreens), part of the monthly savings booklet
EXP: expires on or expiration date
FAC: free after coupon
FAR: free after rebate
GC: gift card
hangtag: an extra tag attached to an item (for instance, hanging around the neck of a hand soap), often a coupon for a discount on that item
IVC: instant value coupon (Walgreens), see ESC
man q: manufacturer's coupon
MC: manufacturer's coupon
MIR: mail-in rebate
OOP: out of pocket (amount paid after all discounts)
OOS: out of stock
overage: the amount of credit left when buying an item for which you have coupons that exceed the price of the item. For instance, if you buy a bottle of shampoo at $2.50 and have a manufacturer's coupon for $2.00 and a store coupon for $1.00, you would have $.50 of overage. Overage is also sometimes used in reference to rebates. In the example provided, if you additionally had a $2.50 mail-in rebate, it would make for a total of $3.00 overage.
P&G: Procter and Gamble, a major manufacturer of many different types of household goods. Procter and Gamble puts out coupon inserts in newspapers on a regular basis, so someone may use this acronym to indicate where they found a particular coupon.
peelies: peel-off coupons or rebates found on an item
roll: when you use discounts earned on one purchase toward your another purchase. For instance, if you earn a $5 Catalina with a makeup purchase, then roll that Catalina to buy cereal which produces a $4 Catalina.
RR: Register Rewards (Walgreens Catalina), may be earned by purchasing specific advertised items and can be used as "Walgreens cash" (may not be applied toward sales tax)
seven-day coupon: store coupons in Walgreens weekly flier
SCR: single check rebate. Refers to RiteAid's rebate program.
stack: when you use a variety of discounts (store sale, store coupon, rebate, and/or manufacturer's coupon) on a single item.
superdouble coupon: generally this is when a store has a certain day where they raise the limit of doubled coupons. For instance, if they normally double up to $1.00, they may double up to $2.00 on their superdouble day.
tearpad: a pad of coupons or rebates usually placed next to the item on the store shelf
TMF: try me free, usually a manufacturer's mail-in rebate
V: Valassis. One of three main newspaper coupon insert companies, the others being RedPlum and SmartSource.
WYB: when you buy
YMMV: your mileage may vary (the details of your deal may work differently)
Special thanks to Mary for her help.
As I mentioned above, please leave a comment if you're puzzled by a term and I'll do my best to help you.