List Only - What does it mean when a part of a car is "locked up"?

What does it mean when a part of a car is "locked up"?

The description on a truck that i want says the 5.7 engine is [LOCKED UP], what does it mean? Take a look, think its worth it?? http://sacramento.craigslist.org/cto/1974945151.html

Public Comments

Seized
Seized The engine is probably shot
"Locked Up" mean the engine is seized, probably due to running with no oil or major overheating. It will probably need replaced.
$1950 for a 22 year old truck with a bad motor is a lot of money. The real problem is you have no way to tell if the rest of the drive train is good, or if there are other problems. The 5.7 motor is common, you could find a used one at a junkyard or buy a rebuilt one, but you have no idea if the transmission, transfer case, and rear are good. I would not want to pay more than $500 for that truck, seeing as it could easily be a money pit
'locked up' means the engine won't turn and that is usually bad. An overhaul or replacement is probably needed.
Ha...lift kit in sacramento. Ha...6k parts in an old ass truck. Ha...seized engine. And you're considering buying it...why? Do you live in the Kentucky part of Sacramento?