(covers information from several alternate timelines)
Hitchhiking was the act of gaining transport by asking others to hitch a ride. One who participated in this practice was known as a hitchhiker.
In 2152, Tucker responded to the theory that a mysterious pod they had picked up was of Human origin but had got a ride from someone, that that would have constituted a hitchhiking record. (ENT: "Future Tense")
In 2373, Odo stopped the limousine of Julian Bashir within the Julian Bashir, Secret Agent holoprogram to talk about Arissa. While stopped, Miles O'Brien (as Falcon) pointed a gun to Bashir's head through an open window and asked whether nobody had told Bashir not to stop for hitchhikers. (DS9: "A Simple Investigation")
In 2375, after One had been created aboard the USS Voyager and began assimilating information, B'Elanna Torres sarcastically asked how many Borg hitchhikers they'd pick up on their journey. (VOY: "Drone")