1. to hold open (Mostly for doors, but also used in a figurative sense of holding the hands open for handouts.)
Opposite (closest): zuhalten
2. to stop (In the sense of stopping something from happening or someone from doing something. Think, super villains or technical progress.)
3. to slow down, to hold up (In the sense of holding up someone, stopping them from progressing. Also used reflexively for contexts of (not) delaing with something - "sich+Acc aufhalten mit")
4. to be/stay at a place ("sich+Acc aufhalten", sounds a bit formal.)
