fall back on
1. Сдавать позицию.
The enemy made a strong attack, and the soldiers fell back on the fort.
2. Оказывать помощь; помогать в нужную минуту.
When the big bills for Mother's hospital care came, Joe was glad he had money in the bank to fall back on.
If Mr. Jones can't find a job as a teacher, he can fall back on his skill as a printer.