Nobody rings first of today's papers (twelve) (8)
I believe the answer is:
noontide
'twelve' is the definition.
(twelve o'clock)
'nobody rings first of today's papers' is the wordplay.
'nobody' becomes 'no one' (I've seen this before).
'rings' is an insertion indicator.
'first of today' becomes 't' (1st letter of 'today').
'papers' becomes 'ID' (identification papers).
't'+'id'='tid'
'noone' placed around 'tid' is 'NOONTIDE'.
(Other definitions for noontide that I've seen before include "Time" , "lunchtime? Certainly" , "12" , "Midday" .)