Realm most disordered? (9)

I believe the answer is:

maelstrom

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

'realm most disordered?' is the definition.
I can't judge whether this defines the answer.

'realm most disordered?' is the wordplay.
'disordered?' indicates anagramming the letters (I've seen 'disordered' mean this).
'realm'+'most'='realmmost'
'realmmost' anagrammed gives 'MAELSTROM'.

Can you help me to learn more?

(Other definitions for maelstrom that I've seen before include "Norwegian whirlpool" , "extreme turbulence" , "disorder" , "Eddy" , "fearsome current" .)

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