Robert K Foster23 May 2003

A block or wedge placed under something else, such as a wheel, to keep it from moving.
Nautical. A heavy fitting of metal or wood with two jaws curving inward, through which a rope or cable may be run.

tr.v. chocked, chock·ing, chocks
To fit with or secure by a chock: The plane's wheels were chocked and chained down.
Nautical. To place (a boat) on chocks.

adv.
As close as possible: had to stand chock up against the railing.

I am confused. very confused.