Confronted with corrosion, he doesn't remain silent (3)

I believe the answer is:

les

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'confronted with corrosion he doesn't remain silent' is the definition.
The definition suggests a singular noun which matches the answer.

This is all the clue.

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(Other definitions for les that I've seen before include "- Dawson, Br. comedian" , "-- Miserables, musical" , "Boy's name (abbr)" , "-- Dawson, English comic" , "French definite article" .)

I've seen this clue in the Evening Standard.

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