on the button
idiomPart ofbutton
on the button — idiom
1. Exactly at the correct time or exactly as stated.
1.idiom
Definition
Exactly at the correct time or exactly as stated.
Example
The train arrived at 9:00 on the button.
Your guess was right on the button; it's exactly 50 dollars.
2. exactly correct, or happening at exactly the right time, with no delay.
2.idiom
Definition
exactly correct, or happening at exactly the right time, with no delay.
Example
The train pulled into the station at six on the button.
Lina's guess about the answer was right on the button.