Just the fellow to galvanise things? (4,4)

I believe the answer is:

live wire

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

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

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(Other definitions for live wire that I've seen before include "isn't it shocking?" , "Conductor charged with electricity - energetic person" , "dynamic chap" , "Life and soul of party" , "Alert and enthusiastic person" .)

I've seen this clue in the Evening Standard.

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