An expression of frustration, usually when one has already done something many times before and is irritated to have to do it again. "Umpteenth" means an indefinitely or innumerably large amount, usually used for sarcastic or hyperbolic emphasis, as in this phrase.

What does for the umpteenth time mean?

From Longman Dictionary of Contemporary Englishump‧teenth /ˌʌmpˈtiːnθ◂/ adjective [only before noun] if something happens for the umpteenth time, it happens again after having happened many times before – used when you are annoyed that it has happened so often 'This is crazy, ' she told herself for the umpteenth time.

What does the phrase umpteenth mean?

Umpteen usually describes an indefinite and large number or amount, while the related umpteenth is used for the latest or last in an indefinitely numerous series.