The most common and most likely answer to this crossword clue is the 10 letter word ADVERTISER
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More clues leading to the result ADVERTISER
- Hyper? Arrange sedative and R&R
- Promoter backs it through unfavourable run
- She plugs electrical radio telephone leads into monitor
- Promoter and mentor keeping Egyptian leader right
- Varied rates putting off a dodgy purchaser of space in newspaper
- He announces drivers’ tea break
- Part of a newspaper’s title? Readers initially voted it changed
- Puffer train driver’s tea …
- Traders — I’ve upset one located on Madison Avenue, maybe
- Publicist arrived, set to get agitated
Buddy explains!

The straight part
We know that "Puffer" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case puffer = advertiser.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 ADVERTISER mean?
ADVERTISER noun- One who advertises.
- A periodical in which advertisements can be published by individuals.