English definition of “back”
SUPPORT [T] › to give support or help to a person, plan, or idea: He backed Mr Clark in the recent election. Parents backed the idea by more than two to one.
MONEY [T] › to risk money by saying that you think a horse, team, etc will win a race, game, or competition in order to win more money if they do: Many people are backing Holyfield to win the fight.
back (sth) away/into/out, etc › to move backwards or drive backwards: She saw he had a gun and backed away. He backed into a wall when he was trying to park.