sleep on something, to

sleep on (something)

To postpone a decision until the following day so that one has additional time to consider it. Why don't you sleep on the offer and let us know your decision in the morning? I'm still not sure if I'm ready to spend that much money. Can I sleep on it?
See also: on, sleep
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

sleep on something

Consider something overnight before deciding, as in I don't know if I want to go on such a long hike; let me sleep on it. This usage was first recorded in 1519 in the state papers of King Henry VIII: "His Grace ... said that he would sleep and dream upon the matter."
See also: on, sleep, something
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

sleep on something, to

To postpone a decision until the next day. Both the idea and the expression are very old. The State Papers of HenryVIII (1519) by an unknown compiler stated, “His Grace . . . sayd thatt he wold slepe and drem upon the matter.”
See also: on, sleep, to
The Dictionary of Clichés by Christine Ammer Copyright © 2013 by Christine Ammer
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