RETURNING › where someone or something was before: I'll be back in Sydney on the 20th. When do you go back to college? I put it back in the cupboard.
BEHIND › in a direction behind you: Anna stepped back. Flint leaned back in his chair.
REPLY › as a reply or reaction to something: UKto ring back/US to call back I signalled to her and she waved back.
STATE › to the state something or someone was in before: Hopefully things will get back to normal again now. I'm sure we can put it back together again (= repair it). Try to go back to sleep.
EARLIER › at or to an earlier time: We first met back in 1973. Looking back, I think we did the right thing.
AWAY FROM › in a direction away from something: He pulled back the curtain. The house was a short distance back from the road.
back and forth (also UK backwards and forwards) › in one direction, then the opposite way, then in the original direction again many times: He has to travel back and forth between London and Paris every week.