on_the_button
1. [ adverb ] just as it should be
Synonyms: precisely exactly on_the_dot on_the_nose
Examples:

"`Precisely, my lord,' he said"

2. [ adjective ] being precisely to a prescribed or specified criterion
Synonyms: on_the_nose
Examples:

"his guess was on the nose" "the prediction for snow was right on the button"

Related terms: precise
Similar spelling:   on_the_fence
  on_the_books
  on_the_offensive
  on_the_fly