Calm bully teased by head (10)

I believe the answer is:

sedateness

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

'calm' is the definition.
The definition and answer can be both human attributes as well as being singular nouns.
Perhaps there's an association between them I don't understand?

'bully teased by head' is the wordplay.
'bully' is an anagram indicator (I've seen this in other clues).
'by' is a charade indicator (letters next to each other).
'head' becomes 'ness' (ness is a headland).
'teased' is an anagram of 'sedate'.
'sedate'+'ness'='SEDATENESS'

Can you help me to learn more?

I've seen this clue in The Independent.

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