refers to a situation in which an undesirable candy bar in a vending machine is blocking access to the desirable candy bar behind it.
Dammit! I was jonesing for some peanut M&M's but I got choc-blocked by that Almond Joy bar that's been sitting in front of them for the past three weeks!
it is when you have anal sex with someone, then pulling out your penis which is covered in their shit and then getting your shit covered penis sucked, blowjob.
After having anal sex
Matilda: wow that was great
Nathaneal: ready for desert?
Matilda: mmm... is it your choc top?