Flag almost associated with Eire

I believe the answer is:

iris

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'flag' is the definition.
(type of iris flower)

I don't understand the rest of the clue.

(Other definitions for iris that I've seen before include "Pupil's place?" , "Flower - rainbow" , "Eye part or pretty flower" , "Coloured eye part" , "Eye diaphragm" .)

I've seen this clue in The Daily Mail.

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