La penúltima pregunta

[ROBINDESBOIS]

In English?
The last but one question ?
Any other possibilities?

[Perikles]

In English?
The last but one question ?
Any other possibilities?Yes: The penultimate question.

If it was the last but two question, you could say the antepenultimate question.

[Rusty]

'Last but one', 'last but two', etc. are BrE usages. FYI, here are the AmE equivalents:

ultimate:
the last (question)

penultimate:
the next-to-the-last
the next-to-last
the second-to-the-last
the second-to-last

antepenultimate:
the third-to-the-last
the third-to-last

preantepenultimate:
the fourth-to-the-last
the fourth-to-last

[ROBINDESBOIS]

Thanks.