What does the expression "Encore my a*s*s" mean?

"my a*s*s" or, more euphemistically, "my foot", means something like "I don't think so", or "you wish", expressing strong disbelief of an information received or aversion to do as asked to. So your example sentence could be

1) either the answer to a question such as 'And did they ask you for an encore?' - "Encore my foot, they started booing while I was still playing"

or

2) the rude refusal of a musician to give an encore after their performance: "Encore my foot, I've got a plane to catch"

And yes, "I'm not cut for this and that" means same as "I'm not made for this and that"

again my backside

some mingling of English and French the *s are used to prevent Yahoo from replacing the letters with stars - just learned that if you write the word without stars there will be only stars - like the beeps in TV shows

It's just a way of saying "no, I'm not going to repeat myself, or I'm not doing it again" because 'encore' means again.

encore means to repeat so it must mean to repeat my *** over and over again lol.If someone said it to you and not subjective to themselves....then I would say they want to eithr beat you up over and over lol since they use the cursing to emphasize anger unless of course thats how they usually talk otherwise they could be talking about repeating you in some way....

It means look at a reflective mirror and examine your ....!

@ sami: do you know non-reflective mirrors before giving your holy opinion here?