on the verge of

on the verge of (doing) (something)

Closely approaching some action or outcome; very nearly at the point at which something will happen. After weeks of failed experiments, I think we're finally on the verge of a breakthrough.
See also: of, on, verge
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

on the verge of

Close to, on the brink of, as in I was on the verge of calling the doctor when he suddenly got better, or Sara was on the verge of tears when she heard the news. This term uses verge in the sense of "the brink or border of something." [Mid-1800s]
See also: of, on, verge
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

on/to the verge of something/of doing something

at or close to the point or time when somebody does something or something happens: She was on the verge of tears.We’re on the verge of signing a new contract.
See also: of, on, something, to, verge
Farlex Partner Idioms Dictionary © Farlex 2017
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References in periodicals archive ?
Record-breaking Daw Mill Colliery, near Nuneaton, is on the verge of a pounds 100million-plus investment programme which promises to safeguard its future for years.