Singular bravery, dismissing a source of torment (7)
I believe the answer is:
scourge
'source of torment' is the definition.
'scourge' can be an answer for 'torment' (I've seen this before). I'm unsure of the 'source of' bit.
'singular bravery dismissing a' is the wordplay.
'singular' becomes 's' (abbreviation in grammar).
'bravery' becomes 'courage' (synonyms).
'dismissing' indicates named letters should be taken away.
'courage' with 'a' taken away is 'courge'.
's'+'courge'='SCOURGE'
Can you help me to learn more?
(Other definitions for scourge that I've seen before include "Bane, curse" , "Person/thing causing great suffering; whip" , "menace" , "Punish severely" , "Harass" .)