Calm way with ailment (9)
I believe the answer is:
stillness
'calm' is the definition.
(thesaurus)
'way with ailment' is the wordplay.
'way' becomes 'st'.
'with' says to put letters next to each other.
'ailment' becomes 'illness' (I've seen this before).
'st'+'illness'='STILLNESS'
(Other definitions for stillness that I've seen before include "Lack of activity" , "Lack of movement" , "Immobility" , "Tranquillity, calm" , "Tranquil silence, calmness" .)