The most common and most likely answer to this crossword clue is the 7 letter word CORDIAL
C
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R
D
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The straight part
We know that "Warm" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case warm = cordial.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 CORDIAL mean?
CORDIAL noun- A concentrated noncarbonated soft drink which is diluted with water before drinking.
- An individual serving of such a diluted drink.
- A pleasant-tasting medicine.
- A liqueur prepared using the infusion process.
- A candy (or bonbon) usually made of milk chocolate, filled with small fruits (often maraschino cherries) and syrup or fondant.
- Anything that revives or comforts.
- Hearty; sincere; warm; affectionate.
- Radiating warmth and friendliness; genial.
- Tending to revive, cheer, or invigorate; giving strength or spirits.
- Proceeding from the heart.