Extra accepting Oscar for ace? Strange! (8)
I believe the answer is:
unwonted
'strange' is the definition.
(thesaurus)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for unwonted that I've seen before include "Out of the ordinary, uncommon" , "Unaccustomed" , "Not habitually" , "Atypical, not usual" , "not typical" .)