What does "stick up" mean?

Project from a surface, as in That little cowlick of his sticks up no matter what you do. [Early 1400s]

Put up a poster or notice, as in Will you stick up this announcement on the bulletin board? [Late 1700s]

Rob, especially at gunpoint, as in The gang concentrated on sticking up liquor stores and gas stations. This usage, dating from the mid-1800s, gave rise to the colloquial phrase, stick 'em up, a robber's order to a victim to raise his or her hands above the head. [1930s]