not to mention

not to mention idiom
Also, not to speak of; to say nothing of. In addition to, besides what's already been said. For example, I don't think the voters will want that big program, not to mention the cost, or Dave teaches trumpet and trombone, not to speak of other brass instruments, or Their house is worth at least a million, to say nothing of their other assets.

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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