Labour accepting quorum periodically creates disorder (7)
I believe the answer is:
turmoil
'disorder' is the definition.
(I know that turmoil is a type of commotion)
'labour accepting quorum periodically' is the wordplay.
'labour' becomes 'toil' (synonyms).
'accepting' indicates putting letters inside (inserted letters are accepted).
'periodically' indicates alternate letters (letters must be selected 'every so often').
The alternate letters of 'quorum' are 'urm'.
'toil' going around 'urm' is 'TURMOIL'.
'creates' acts as a link.
(Other definitions for turmoil that I've seen before include "upset" , "Disquiet" , "Pandemonium" , "Violent commotion" , "State of great commotion or disturbance" .)