Head of innovation in store nearly resigned (5)

I believe the answer is:

stoic

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'resigned' is the definition.
(I've seen this before)

I don't understand how the rest of the clue works.

(Other definitions for stoic that I've seen before include "One patient under misfortune" , "One indifferent to fortune, pleasure and pain" , "Solemn ceremony" , "Long-suffering type; follower of Zeno" , "One who endures pain with equanimity" .)

I've seen this clue in The Guardian.

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