on somebody's say-so

on (one's) say-so

With or according to one's authorization or permission. Although I'm the manager of this department, I can only make changes to the way things run on the general manager's say-so. A: "We're going to start transferring the funds into the new account." B: "On whose say-so?"
See also: on
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

on somebody’s ˈsay-so

based on a statement that somebody makes without giving any proof: He hired and fired people on his partner’s say-so.
See also: on
Farlex Partner Idioms Dictionary © Farlex 2017
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