Swelling small yet disastrous (4)

I believe the answer is:

stye

'swelling' is the definition.
(stye is a kind of swelling)

'small yet disastrous' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'disastrous' is an anagram indicator.
'yet' anagrammed gives 'tye'.
's'+'tye'='STYE'

(Other definitions for stye that I've seen before include "Eye sore" , "nasty spot" , "Animal pen" , "irritation to the viewer" , "Inflamed swelling on the edge of an eyelid" .)

I've seen this clue in The Sun.

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