The most common and most likely answer to this crossword clue is the 6 letter word CYGNET
I've seen this crossword clue in Financial Times
C
Y
G
N
E
T
More clues leading to the result CYGNET
- The Swan’s tragic play: starting in Elsinore, it ends there
- Extremely clumsy snare trapping tail of young bird
- Water-loving youngster — small seal, reportedly
- Sound made by small seal or young 17
- Small seal picked up young swimmer
- Ring, say, a young bird
- Young winger, on the fringes for City, getting rise of ten grand
- Young bird starts to chirp – you get nervous, excited, tense
- Caught and gently treated missing large young bird
- It’s not part of city gent’s choreographed minor ballet role
Buddy explains!
The straight part
We know that "Grey animal swimming" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case grey animal swimming = cygnet.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 CYGNET mean?
CYGNET noun- The young of a swan.