someone who is amazingly good at any sport he/she tries. someone who is popular because of sports, but doesn't have enough money to be a prep. most of the time,they use that to take advantage of something (i.e.- class officer elections)
Bob (the jock in this) is really popular and tries to wear preppy clothes, but just doesn't have enough money to actually fit in with the preps. (POOR BOB)
esp. a scornful term used to convey a particularexpression of disgust at the exceptional state of disrepair/bad condition of the item under discussion.
"That yoke's in a fucking jock" Hench exclaims as we pull up to view a 1989 zxr400 motorcycle which was described as 'in good condition' on ebay after driving 65miles. And promptly leave.