The most common and most likely answer to this crossword clue is the 5 letter word STYES
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S
Buddy explains!
The straight part
We know that "Swellings troubling your eyes, say, initially" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case swellings troubling your eyes, say, initially = styes.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 STYES mean?
STYES noun- A ladder.
- An inflammation of the eyelid.
- A bacterial infection in the eyelash or eyelid.