1
general::
Phrase(s): set something back [and] put something back
to set something, like a timepiece, to a lower number. (Put is less common.) • It’s that time of year when you must set your clocks and watches back! • Set back your clock tonight. • I have to put all the clocks back., Phrase(s): set someone back (some amount of money)
to cost someone (an amount of money). • This coat set me back about $250. • That fancy dinner at the restaurant last night really set us back.
McGrawhill's American Idioms And Phrasal Verbs
2
general::
1. Slow down the progress of, hinder, as in The project was set back by the frequent absences of staff members. [First half of 1500s] 2. Cost, as in That car set me back twenty thousand dollars. [Colloquial; c. 1900] 3. Change to a lower level or earlier time, as in We set back the thermostat whenever we go on vacation, or On October 10 we have to set back the clocks. [First half of 1600s] Set back the clock is Also used figuratively to mean "return to an earlier era," as in He wished he could set back the clock to those carefree highschool days. Also see SET FORWARD.
American Heritage Idioms