half·sies or halv·sies 
(hăvzēz, häv-)
(hăvzēz, häv-)pl.n.
Slang
Slang
Used following the verb go to indicate that two people are equally sharing the expense for something: Let's go halfsies on the dinner bill.
[Probably alteration of earlier halvers, from halver, a half share, from HALVE.]