Flipping someone the bird or giving someone the middle finger.
Econo as in economy, meaning
thrifty management. Normally a wave utilizes all five fingers of the hand. In an
econo wave, a person is conserving the number of fingers used in order to give someone just a one-fingered wave (i.e. the middle finger).
Britney: As I was driving down
I-95, I saw one of those trash pickup crews on the side of the highway. I wanted to contribute to their effort, so I threw my Mickey D's
bag out the window and onto the grass for them. One of the guys saw me and gave me the
econo wave.