The correct answer is (C) A gliding step in dancing; a sliding dance step. Also, a controlled slide down a steep snowy or icy slope, as on skis or a toboggan.

Glissade comes from French glisser (to slide).

Examples of use:

• A series of glissades brought them to a lower elevation in rapid time.
• Graceful glissades and pointing arms, as well as music, identify the tango.