1 definition by JC, quoting Jimmy The Greek

When shelfing (or shelving- i.e inserting something in your rectum, usually ecstasy for increased absorption rate) the way that one knows they have done so correctly.
Go in with your finger and curl it back over- place it on the top shelf.
Dude: Here man shelf this.

Other Dude: ...... I've never done that before.......how do i, you know, know its in the right spot.

Dude: Up and over- top shelf. (Whilst doing up and over motion with index finger.)
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