Messy classes are unavoidable, despite our best efforts. So, perhaps we should make lemonade and think of off days as a unique subset of ballet with its own rules and definitions. (Apologies in advance to ballet teachers worldwide.)
Arabesque à la Seconde: The proper name for “a la sebesque”.
Hawaiian Rond de Jombe: Yes, it’s correct technique to include a little hula.
Petrushka Jumps: Pointed feet and stretched knees would just spoil the effect.
Port de Bras de Coppélia: The ability to move like an emotionless, mechanical doll can be invaluable.
“Reverse”: Dance historians now believe this originally meant “take a moment to freestyle”.
Runway Updo: A messy bun is fashionable after all.
Spotting: The critical skill of whipping your head around to see just-what-on-earth-is-everyone-else-doing-anyway.
Superman Penchée: Arching your back would ruin the streamlined look. So would lifting your leg above 90 degrees:
Tombé: The correct way to arrive on the floor…
Variation: As in your own personal variation of whatever the combination was supposed to be…
Vibrato: A sophisticated addition to any balancing exercise.
Zombé: Any step performed with an appropriately dead level of energy.