The most common and most likely answer to this crossword clue is the 4 plus 5 letter word MONT BLANC
I've seen this crossword clue in The Guardian
M
O
N
T
B
L
A
N
C
More clues leading to the result MONT BLANC
- A lot of March, say, mostly clear and cold for skiing area?
- Can early bet inform odds, when backing one to get up?
- Million British pounds put in cannot offset peak of continental Europe
- It’s high time to face second-rate student taken in by conman abroad
- Developing tan on climb, one left mountain
- Con man on the run consumes BLT preparation in the peak of European tourism
- Bonn calm after rioting about temperature peak in Europe
- Monsieur altered canton to include limits of Basel and an Alp
- Mountain climb, not an easy one abandoned
Buddy explains!

The straight part
We know that "one to get up?" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case one to get up? = mont blanc.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.