on the up-and-up


Open and honest, as in Dad has always been on the up-and-up with them. The precise allusion in this term is unknown. [Colloquial; c. 1860]

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.