sell someone on

sell (one) on (something)

To convince or persuade one to do something or to accept some plan or idea. Often used in passive constructions. I can't believe he sold me on another one of his harebrained schemes. I just don't like the way their customer service agents try to sell you on extra policies or more expensive packages—that's the sales team's job. I wasn't sold on the idea until they showed me exactly how they planned to spend the money.
See also: on, sell
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

sell someone on

Convince or persuade someone of the worth or desirability of something, as in They were hoping to sell enough legislators on their bill so that it would pass easily, or Dave was really sold on that new car. [Colloquial; early 1900s]
See also: on, sell, someone
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.
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