Illiterate design or a museum piece? (9)

I believe the answer is:

ignoramus

'illiterate' is the definition.
(thesaurus)

'design or a museum piece?' is the wordplay.
'piece?' says the answer is hidden in the clue (I've seen 'piece' mean this).
'IGNORAMUS' is hidden in the letters of 'design or a museum'.

(Other definitions for ignoramus that I've seen before include "Stupid person" , "One could be blissful it's said" , "I wouldn't know" , "Ron is a mug (anag.)" , "Imbecile" .)

I've seen this clue in The Telegraph.

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