Definitions
1.verbTo rob at gunpoint."I think they intend to stick up the bank."
2.verbTo be prominent; to point upwards."No matter how much I brush it, my hair always sticks up."
3.verb(with for) To speak or act in defence (of)."Don't let them push you around, stick up for yourself."
4.verb(with to) To defy, to confront, to stand up to.
5.verb(with to) To maintain a commitment (as, to a proposition or role)