Swimming style in which Adam Peaty specialises (12)
I believe the answer is:
breaststroke
This might be a double definition.
'swimming' is the first definition.
(thesaurus)
'style in which adam peaty specialises' is the second definition.
'breaststroke' can be an answer for 'style' (I have seen 'Natant style' mean 'breaststroke' so perhaps 'style' could also mean 'breaststroke'). I'm not certain of the rest of the definition.
Can you help me to learn more?
(Other definitions for breaststroke that I've seen before include "What swimmers may do" , "Natant style" , "Adam Peaty's swimming style" .)