Ok, so you were speaking technically correctly to clarify the term. Just FYI, I have a degree in Electrical Engineering and I've done a decent amount of work with pro sound equipment and have spent time in a recording studio. I know what phase differences are.
That being said, the "industry term" is "phase reversal" or "180 degrees out of phase". I've worked in the audio business as well and that's the term that's used all over. Whether it's right or not.
This might be analogous to a situation I had once. A guy from a car mechanic (and customization) shop came over and asked us (the place I worked at) for sound deadening material. He said it couldn't be more than 2 mils thick. Mils, in measurement, means thousands of an inch. Two mils is 0.002 inches in thickness. All of our material was substantially thicker. After 10 minutes of back and forth and calling someone at his shop, we figured out that he was using the car industry term: Mils == millimeters! "Hey hand me that 10 mil socket." We sold him the material and all was good.
When I hear "out of phase" I know it means polarity. When I hear 90 degrees out of phase, I know it's a time shift which corresponds to a specific frequency with a 1/4 wavelength. But really, no one uses that term. Time delays, in the audio industry are specified in milliseconds or alternatively in feet or meters.
Brian.