When you wave to someone you know and another person intercepts your wave mistakenly as if you are waving to them, e.g. caught in the crossfire of your wave.
I was waving to Eddy at the show and Phil thought I was waving to him. Awkward... Phil waved back to me as he was caught in a whoopsie wave. It's almost as bad as when Jim invited me to lunch, thinking I was Tony because his phone contacts were screwed up resulting in Jim texting me with an invite.