- to make or become straight in direction, form, position, character, conduct, condition, etc. (often followed by up or out).
Origin of straighten
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- to become or cause to become erect
- mainly US to reform or become reformed
- to make or become straight
- (tr) to make neat or tidystraighten your desk
Word Origin and History for straighten up
Online Etymology Dictionary, © 2010 Douglas Harper
Idioms and Phrases with straighten up
Make tidy, as in Let's get this room straightened up. [Second half of 1800s]
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.