Inside the UK, the phrase coarse fish represents any style of freshwater fish aside from trout, salmon and char. Kinds include barbel, bream, carp, chubb, dace, ide, pike, perch, rudd, roach, zander, Wels catfish, and tench. Several fishermen who look for these kinds of fish use special coarse fishing tackle and see themselves as specimen hunters. According to Wikipedia (paraphrased):

The phrase "coarse fishing" began in the UK in the early 1800s. Previous to that time, leisurely fishing was a sport of the gentry, who angled for trout and salmon which they named "game fish". Various other fish were rejected as "coarse fish."