Spring of rib - You want the ribs to come out of the spine more horisontal before it starts to slope down, this will create a bigger barrel that is wider over the top. This is especially significant in the heart girth area. The more capacity there, the more opportunity for optimal heart and lung function. More spring of rib usually also means more rumen capacity meaning the animal can consume more low quality roughage that is slow to digest, so a more roomy animal will be an easier keeper in tough times
Roofy - when looking at an animal from behind you want a more or less level rump, this indicates more muscle and more potential muscle in the case of an animal in lower condition. When there is a significant slope from the tailhead to either side it resembles a roof, hence the term roofy.
Cow hocked - When the hocks of an animal points inwards when seen from behind. It's a structural flaw often seen in narrow based animals.
