The most common and most likely answer to this crossword clue is the 6 letter word GRATES
G
R
A
T
E
S
Buddy explains!
The straight part
We know that "jars" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case jars = grates.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 GRATES mean?
GRATES noun- A horizontal metal grill through which water, ash, or small objects can fall, while larger objects cannot
- A frame or bed, or kind of basket, of iron bars, for holding fuel while burning
- To furnish with grates; to protect with a grating or crossbars
- To shred (things, usually foodstuffs), by rubbing across a grater
- To make an unpleasant rasping sound, often as the result of rubbing against something
- (by extension) to get on one's nerves; to irritate, annoy
- (by extension) to annoy