The most common and most likely answer to this crossword clue is the 7 letter word DUNKING
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The straight part
We know that "Immersing" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case immersing = dunking.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 DUNKING mean?
DUNKING noun- The act or process of briefly submerging or immersing an object or person in a liquid, as in dunking a cookie in milk, or dunking a playmate in the swimming pool.
- Forcefully thrusting the ball through the basket from above.