Girl’s wrath and anger oddly vanishing (5)
I believe the answer is:
irene
'girl's' is the definition.
(I've seen this before)
'wrath and anger oddly vanishing' is the wordplay.
'wrath' becomes 'ire' (both can mean anger).
'and' is a charade indicator (letters next to each other).
'oddly vanishing' means one should take alternating letters (letters in odd-numbered positions removed).
The alternating letters of 'anger' are 'ne'.
'ire'+'ne'='IRENE'
(Other definitions for irene that I've seen before include "woman" , "Peaceful girl" , "Female name" , "- - Handl, actress" , "One can find a girl in Ree" .)