The most common and most likely answer to this crossword clue is the 4 letter word DONG
I've seen this crossword clue in The Guardian
D
O
N
G
More clues leading to the result DONG
Buddy explains!

The straight part
We know that "Shiny-nosed character/sound as a bell" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case shiny-nosed character/sound as a bell = dong.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 DONG mean?
DONG noun- The currency of Vietnam, 100 xus. Symbol: ₫
- A penis.
- (by extension) A dildo, specifically a synthetic anatomical replica of the penis.
- Onomatopoeia for the ringing sound made by a bell with a low pitch.
- Of a bell: to make a low-pitched ringing sound.
- A submunicipal administrative unit of a city in North or South Korea.