How is “flat out” used?

In All the President's Men (1976), one line is: “No, we were never told flat-out, "Don't talk."”

Which movie is “flat out” from?

The clip at the top of this page is from All the President's Men (1976).

No, we were never told flat-out, "Don't talk."

8 作品で登場 · 1 本目

in a definite and direct way; completely; as fast or as hard as possible

アメリカ英語 · 18 本の映画に登場

オックスフォード映画の 80%
in a definite and direct way; completely
It's flat-out spoiling him.
No, we were never told flat-out, "Don't talk."
オックスフォード映画の 20%
as fast or as hard as possible

定義：Oxford Advanced Learner's Dictionary 第 9 版