A combination of WiFi, the popular wireless technology, and a high five, a celebratory gesture made between two people.
WiFi's are made when the two people performing are too far away to physically connect a high five and instead perform the motions of one without actually touching.
The instigator should announce 'WiFive!' before acting it out so as to not cause confusion.
WiFi's may or may not be accompanied by a 'whoopish' noise in order to make the gesture more realistic.
If your really nerdy and someone fails to realise the WiFive or tries to reach for a real high five and fails then they may be taunted by everyone around them making the old 56Kb dial up noise really loud in their face.
I went to give Pubert a WiFive yesterday over the Grand Canyon but he thought I said high five and tried to reach over. Needless to say he fell down the 1.6 km drop and I went...
Booooooooo ba da da ba ba da da ba da ba da bee Bee bada biiiir beeeeeeeeeee aa eeeeeeeeeeEEEEEEEEEEEEEEEEEEE bir BIR bow dow bow dow bow EEEEEEEECKKKKKKKKKKKKKKKKKKK AAAAACKKKKKKKKKKKKKKKKKKK AAAAAAAAAAAAAAAAAAAAAAAGH PHffffffffffFFFFFFFFFFFFFFFFFFT