It’s the use of “protest vote” period. If you vote your conscience for the person and the party that best represents you it will never be a protest.
If you don’t vote. You can call that a protest, but not voting means it’s not a “protest vote” because no vote was cast.
If you vote against Hillary, and normally would vote Democratic, then that might be a protest vote. Still each case is an individual instance.
The bottom line is arguing over this at this point in time is immensely counter productive. Let’s talk strategy for moving forward with the immanent change. Carrying on about who voted which way and why is a distraction from very, necessary organizing.