Clipping of howdy-do, from how-d'ye-do (“how do you do”).
Meanings
(transitive) To greet informally, especially by saying "howdy"
I stood up for the kid and it got ugly, with accusations being thrown in both directions. So the sheriff and I weren't exactly on howdying terms when that fire happened. 2016, Brynn Bonner, Dead in a Flash, page 249: