Idioms and Phrases with least of all
least of all
Especially not. For example, No one cared, least of all the manager, or None of them will attend, least of all Jim. [Late 1800s]
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.