The most common and most likely answer to this crossword clue is the 7 letter word FLIPPER
I've seen this crossword clue in Independent
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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.
What does FLIPPER mean?
FLIPPER noun- In marine mammals such as whales, a wide flat limb, adapted for swimming.
- A flat, wide, paddle-like rubber covering for the foot, used in swimming.
- A flat lever in a pinball machine, triggered by the player to strike the ball and keep it in play.
- A small flat used to support a larger one.
- A type of ball bowled by a leg spin bowler, which spins backwards and skids off the pitch with a low bounce.
- Television remote control, clicker.
- The hand.
- A kind of false tooth, usually temporary.
- A kitchen spatula.
- Someone who flips, in the sense of buying a house or other asset and selling it quickly for profit.
- Someone who flips in any other sense, for example throwing a coin.
- To lift one or both flippers out of the water and slap the surface of the water.