The most common and most likely answer to this crossword clue is the 9 letter word TENDEREST
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The straight part
We know that "Most gentle" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case most gentle = tenderest.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 TENDEREST mean?
TENDEREST adjective- Sensitive or painful to the touch.
- Easily bruised or injured; not firm or hard; delicate.
- Physically weak; not able to endure hardship.
- (of food) Soft and easily chewed.
- Sensible to impression and pain; easily pained.
- Fond, loving, gentle, sweet.
- Young and inexperienced.
- Adapted to excite feeling or sympathy; expressive of the softer passions; pathetic.
- Apt to give pain; causing grief or pain; delicate.
- Heeling over too easily when under sail; said of a vessel.
- Exciting kind concern; dear; precious.
- Careful to keep inviolate, or not to injure; used with of.