Crossword Genius

Turn under grim feature of paddle-boat (5,5)

Ross

I believe the answer is:

stern wheel

I'm a little stuck... Click here to teach me more about this clue!

'feature of paddle-boat' is the definition.
I don't know anything about this answer so I can't judge whether it can be defined by this definition.

'turn under grim' is the wordplay.
I cannot really see how this works, but
'turn' could be 'wheel' (I've seen this before) and 'wheel' is found in the answer.
'grim' could be 'stern' (synonyms) and 'stern' is found in the answer.
No letters remain.
This may be the basis of the clue (or it may be nonsense).

Can you help me to learn more?

I've seen this clue in the Sydney Morning Herald.
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