3 way matching is to compare three documents i.e.,
1. Purchase order
2. Receipt of Items/Packing slip
For example, if we Order for 50 Items in purchase order and received 40 Items only instead of 50 items. But we received invoice for 50 items. After comparing the three documents we pay for only 40 Items..
There is no specific abbreviation for the term WIRE because when the payment is being made using this option, you will not see the physical movement of funds. It is all electronic. It is just like a current passes through Wire.
Therefore Electronic movement of funds is campared with WIRE.