The most common and most likely answer to this crossword clue is the 7 letter word IMMERSE
I've seen this crossword clue in The Times
I
M
M
E
R
S
E
More clues leading to the result IMMERSE
- Duck swimmer sees, partially
- Dip huge — right to replace knight
- Engross tail end of form in this writer’s language
- Plunge in river cut short after one minute
- Duck swimmer secretly shows off
- Plunge in Mersey cut short after one minute
- Dip tongue not very far at first?
- Put into liquidation
- Jimmy discovered Irish duck
- Plunge right into nameless giant
Buddy explains!

The straight part
We know that "Dip" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case dip = immerse.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 IMMERSE mean?
IMMERSE verb- To put under the surface of a liquid; to dunk.
- To involve or engage deeply.
- To map into an immersion.
- Immersed; buried; sunk.