Conditional Turn Based always made sense to me, if you take turn as an individual meaning, instead of a global meaning (i.e., turn is action, not turn for every character in the battle). Whomever takes turns is based on certain conditions (speed, actions used, etc.).
Of course, I am weird, so that might be why I find it easy to understand >_>
Clock-tick, in general, to someone not familiar with mechanics, makes no sense. I think the CTB meaning makes more sense than Clock-Tick.