The most common and most likely answer to this crossword clue is the 7 letter word NUNATAK
I've seen this crossword clue in The Times
N
U
N
A
T
A
K
More clues leading to the result NUNATAK
Buddy explains!
The straight part
We know that "something outstanding in white" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case something outstanding in white = nunatak.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.
What does NUNATAK mean?
NUNATAK noun- A mountain top or rocky element of a ridge that is surrounded by glacial ice but is not covered by ice; a peak protruding from the surface ice sheet.