Rent time was important when month’s missed (8)
I believe the answer is:
tattered
'rent' is the definition.
(thesaurus)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for tattered that I've seen before include "Ragged and threadbare" , "Torn and ragged" , "Old and torn" , "Frayed" , "Shabby" .)