The most common and most likely answer to this crossword clue is the 7 letter word SNOWDON
I've seen this crossword clue in The Times
S
N
O
W
D
O
N
More clues leading to the result SNOWDON
- After Scotland's peak, now master Welsh mountain
- Fellow with TV spots royal photographer
- First of skiers immediately departs on mountain
- Photographer has similar facility to that of 17
- Son got over Russian river and mountain
- Boy keeps tumbling down mountain
- Photographer’s mount
- Mountain poles and fleece obtained by individual
- Today, surrounded by signs of approval, climbing mountain
Buddy explains!

The straight part
We know that "mountain" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case mountain = snowdon.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.