Poem, great accomplishment, read out (5)

I believe the answer is:

haiku

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'poem' is the definition.
(I know that haiku is a type of poem)

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

(Other definitions for haiku that I've seen before include "Type of Japanese poem" , "Seventeen-syllable Japanese poem" , "Pithy lines" , "Jap 17-syllable poem" , "Stylised Japanese poem of 17 syllables" .)

I've seen this clue in The Sun.

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