Bangs that have noticeably longer tapering extremities than the main bunch, going at least to eye-level, giving the appearance of hair "fangs". The "fangs" have to be on the sides of the bangs and are basically extensions of the outer edges of the bangs.
The difference between fanged bangs and sidelocks is that fanged bangs are usually thinner and are clearly part of the bangs, not the sides of the hair, while sidelocks are usually thicker and come from the top and the sides of the hair.
The tag also applies when only one side of the bangs is fanged.