Communications in a disorderly state for a very long time (8)
I believe the answer is:
messages
'communications' is the definition.
(message is a kind of communication)
'disorderly state for a very long time' is the wordplay.
'disorderly state' becomes 'mess' (I've seen this before).
'for a very long time' becomes 'ages' (I've seen this before).
'mess'+'ages'='MESSAGES'
'in a' is the link.
(Other definitions for messages that I've seen before include "teachings" , "Shopping up north" , "Communications, written, spoken or signalled" , "Notes" , "Brief communications" .)