A smile's chance outcome (7)

I believe the answer is:

aimless

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

'chance outcome' is the definition.
'aimless' can be an answer for 'chance' (thesaurus). I am not certain of the 'outcome' bit.

'a smile's' is the wordplay.
'a smile's' can be anagrammed to 'AIMLESS'.
However, I'm not sure how the anagram is indicated.

Can you help me to learn more?

(Other definitions for aimless that I've seen before include "Without purpose or target" , "Haphazard" , "Drifting with no purpose" , "Like characters in 5D {WAITING FOR GODOT]" , "Without purpose, like Melissa" .)

I've seen this clue in The Globe and Mail.

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