In every part or aspect, throughout. For example, I was wet through and through, or He was a success through and through. This idiom originally was used to indicate literally penetration, as by a sword. The figurative usage was first recorded in 1410.
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
How to use through and through in a sentence
I'm a Lindsey Graham guy through-and-through, but having a few Tea Party boys running around up there isn't the end of the world.
The conviction in his stare—its through-and-through conviction—had infected her; and she gave in to it for the moment, crushed.The Dark Flower | John Galsworthy
The staircase has through-and-through ventilation of its own.The Dwelling House | George Vivian Poore
They are all abstractions from the Whole, and of course the “through-and-through” character can not be found in them.
The “through-and-through” philosophy, as it actually exists, reminds many of us of that clergyman.
In abstract systems the “through-and-through” Ideal is realized on every hand.