The most common and most likely answer to this crossword clue is the 9 letter word LIGHTBULB
I've seen this crossword clue in The Times
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More clues leading to the result LIGHTBULB
Buddy explains!
The straight part
We know that "Glower, being the subject of jokes?" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case glower, being the subject of jokes? = lightbulb.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 LIGHTBULB mean?
LIGHTBULB noun- An evacuated glass bulb containing a metal filament which is heated by electrical resistance to produce light.
- (by extension) An article that resembles such a bulb and converts electricity to light by any process.
- Used in reference to the sudden arrival of a realization, an inspiration, an idea, or the like.
- An uninvited third person joining a couple's date who prevents or hinders romantic interactions.