Английский словарь американских идиом - back down

or back off {v.}, {informal} To give up a claim; not follow up a threat. * /Bill said he could beat Ted, but when Ted put up his fists Bill backed down./ * /Harry claimed Joe had taken his book, but backed down when the teacher talked with him./ Syn.: BEAT A RETREAT. Compare: BACK OUT, GIVE IN, GO BACK ON(1).