The terms is taken from the website called Television Tropes and Idioms. I use abstract options in place of the more concrete option of warrior, mage, and rogue since the abstract options could be generalized to more types of fighting games like gun games.
Tank focus on defense and protection of party members.
Damager focus on dealing damage but tend to have weak defense unless the damager class in question could also be used as tank.
Support focus on healing, ally boosting, enermy hindering, or indirect attack.
Utility take roles outside of battle like scout, traveling, lock picking, treasure hunter, or item production.
If I could relate the roles to the Accel World color code, then tank would be green, damager would be purple, support would be white or yellow, and utility would be white.