No robe for fairy king (6)

I believe the answer is:

oberon

I'm a little stuck... Click here to teach me more about this clue!

'fairy king' is the definition.
(I've seen this in another clue)

'no robe' is the wordplay.
'no robe' anagrams to 'OBERON'.
However, I'm not clear how the anagram is indicated.

'for' is the link.

Can you help me to learn more?

(Other definitions for oberon that I've seen before include "Titania's husband" , "Spirited king" , "Shakespearean role" , "King of the fairies (AMND)" , "top charmer!" .)

I've seen this clue in The Irish Independent.

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