The most common and most likely answer to this crossword clue is the 10 letter word MATTERHORN
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More clues leading to the result MATTERHORN
- Mountain concern — something sounding warning?
- Mountain, terrible threat in early part of day
- Concern linked to side of Himalayan mountain
- Steep mountain presenting dire threat in early part of day
- Mountain stuff, something hard
- Before noon, possibly, completely lowering milliner’s cap’s peak
- Instrument blown after affair’s high point
- The thing that blows on a mountain
Buddy explains!

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.