Green’s Dictionary of Slang

hitch-up n.

[hitch (up) v. (1)]
(US)

1. a marriage.

[US]E.N. Westcott David Harum 336: I putty much made up my mind to try another hitch-up.

2. a married couple.

[US]E.N. Westcott David Harum 298: What a nice hitch up they’d make.