The most common and most likely answer to this crossword clue is the 7 letter word LOLLARD
I've seen this crossword clue in Financial Times
L
O
L
L
A
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More clues leading to the result LOLLARD
- Old reformist that makes me crack up and blubber
- Laughing out loud over fat idler
- Expression of amusement over fat religious reformer
- Perhaps ironically, it’s amusing fat old slacker
- Titled chap holding everything up, an idle fellow
- Everyone held back by master, a 14th-century reformer
- Abbreviated text written by fat layabout
- Very funny fat early protestant
- I’m tickled by fat religious reformer
- I'm amused by fat religious reformer
Buddy explains!
The straight part
We know that "religious reformer" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case religious reformer = lollard.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.