The Glossary question,...I can't answer, ain't found it either!!!!LOL's But for your scope question,...Check out what your local Wal-mart has to select from. The Center-Point scopes are a real value, and pretty good to boot for a "Economy" scope. Depending on the severity of 'barrel-droop' your particular rifle has,...the factory one piece that came with it,...if it didn't come with rings?!?!?,.......should be OK to stick with. Other wise you'll either have to shim the scope, or get an adjustable mount. Just remember this,....you'll want to set,...or align the scope with the barrel ( elevation-wise,...if the barrel droops,....shim the REAR ring!!!),...and not the reciever/action of the rifle. Another thing to consider is the harshness of the firing cycle. If it's rough,...and neads a scope stop to eliminate any movement,...you'd be well advised to have it tuned. There are different degrees of tuning,...but from and economical stand point, a lube tune may be all that you need to 'tame' a rough fireing weapon. Just depends on how much you want to invest in the rifle. BTW,...by the way,....welcome to the GTA,...It's A Great Place To BE!!!!! Best of Luck, tjk