A pressing need (4)

I believe the answer is:

iron

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'a pressing need' is the definition.
Although both the answer and definition are singular nouns, I don't understand how they can define each other.

This is the entire clue.

Can you help me to learn more?

(Other definitions for iron that I've seen before include "great strength" , "Smoother - metal" , "A magnet attracts it" , "Strong metal; golf club" , "Press - element" .)

I've seen this clue in The Globe and Mail.

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