Like Elsie, she's optionally out of line (5)

I believe the answer is:

elise

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'line' is the definition.
I don't know anything about this answer so I can't tell whether it can be defined by this definition.

'like elsie she's optionally out' is the wordplay.
'elsie' anagrams to 'ELISE'.
However, I am unsure how the anagram is indicated.

'of' acts as a link.

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