Disorderly place might calm (10)
I believe the answer is:
phlegmatic
'calm' is the definition.
(I've seen this before)
'disorderly place might' is the wordplay.
'disorderly' is an anagram indicator.
'place'+'might'='placemight'
'placemight' anagrammed gives 'PHLEGMATIC'.
(Other definitions for phlegmatic that I've seen before include "Calm; philosophical" , "Unemotional" , "dull and lifeless" , "Unexcitable" , "cool" .)