flat-out

The president came to believe Shamir misled him on the settlement issue, or flat-out lied to him.
The Inside Story of U.S. Meddling in Israel’s Elections|Aaron David Miller|December 4, 2014|DAILY BEAST
His post-mortem that there is no red or blue America was tired and flat-out wrong.
Earth to DNC: Dyspeptic Dad Still Votes, Too|Lloyd Green|November 11, 2014|DAILY BEAST
Let me say, flat out, that Harold Conrad was the single most happening, been-everywhere/done-everything cat I ever met.
The Stacks: Harold Conrad Was Many Things, But He Was Never, Ever Dull|Mark Jacobson|March 8, 2014|DAILY BEAST
Old Don said flat-out that he took the girl for both him and his son.
The Ballad of Johnny France|Richard Ben Cramer|January 12, 2014|DAILY BEAST

More vexing than the short-shrift mentions are the flat-out omissions.
John Sutherland‘s Enjoyable Little History of Literature|Malcolm Forbes|November 29, 2013|DAILY BEAST
It was all like putting a man in a racing car traveling flat out on the Salts in Bonneville, Utah.
What Need of Man?|Harold Calin
It was no use, however, it is next to impossible to throw a man when he is lying flat out as the Brahmin now was.
Sport and Work on the Nepaul Frontier|James Inglis
And now lay down that purse,” he continued briefly, “before I shoot the flat out of your eye.
Silver and Gold|Dane Coolidge
Pigeons were cooing near, and several dogs were lying flat out in the shade which the wide eaves of the house afforded.
Polly|L. T. Meade
He has the term to finish, and certainly you would not have him flat out on his job when the end is in sight.
The Story of Porcelain|Sara Ware Bassett

Other Idioms and Phrases with flat-out

flat out

In a direct manner, bluntly. For example, He told the true story flat out. [Colloquial; mid-1900s]

At top speed, as in She was running flat out to catch the train. [Slang; c. 1930]