The most common and most likely answer to this crossword clue is the 5 letter word JELLY
I've seen this crossword clue in The Guardian
J
E
L
L
Y
Buddy explains!
The straight part
We know that "Sweet" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case sweet = jelly.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 JELLY mean?
JELLY noun- An explosive mixture of nitroglycerine and nitrate absorbed onto a base of wood pulp.
- A dessert made by boiling gelatine, sugar and some flavouring (often derived from fruit) and allowing it to set, known as "jello" in North America.
- A clear or translucent fruit preserve, made from fruit juice and set using either naturally occurring, or added, pectin. Known as "jam" in Commonwealth English.
- A savoury substance, derived from meat, that has the same texture as the dessert.
- Any substance or object having the consistency of jelly.
- A jellyfish.
- A pretty girl; a girlfriend.
- A large backside, especially a woman's.
- A jelly shoe.
- Blood.
- To wiggle like jelly.
- To make jelly.
- A coconut with soft or gelatinous meat inside as well as the meat itself (which is of regular quality if the coconut is immature)
- Jealous.