The most common and most likely answer to this crossword clue is the 9 letter word OCCLUDING
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More clues leading to the result OCCLUDING
Buddy explains!
The straight part
We know that "Jamming" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case jamming = occluding.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 OCCLUDING mean?
OCCLUDING verb- To obstruct, cover, or otherwise block (an opening, a portion of an image, etc.).
- To absorb, as a gas by a metal.