A nice way to say that someone is hot and sexy in a mixed crowd or public setting. Especially when referring that person someone else. Or talking to that person directly without being overtly sexual or graphic.
Did you see that woman in the red dress. Now, that is a "good look". Or to the person directly: "That red dress on you is a "good look"."
1. A chick that is decently looking/attractive in the face, but also has qualities of a nice rack (mostly the rack) and butt that come from her being overweight/fat. Unfortunately she is overweight so she will have a spare tire around her waist as well as thighs that are almost as big as 155mm howitzer shells.
2. Can also be a good looking chick with the same qualities ( rack and butt ) as the above and might not necessarily be overweight, but can be heavyset, or voluptuous.
The hourglass and pear female body shapes are typical examples of the the second definition.