The truth about a late start (4)
I believe the answer is:
real
'the truth' is the definition.
Although both the answer and definition are singular nouns, I cannot see how they can define each other.
'about a late start' is the wordplay.
'about' becomes 'rea' (I've seen this in other clues).
'start' says to take the initial letters.
The first letter of 'late' is 'l'.
'rea'+'l'='REAL'
Can you help me to learn more?
(Other definitions for real that I've seen before include "Certainly no counterfeit" , "Existing, not imaginery" , "Actual and tangible" , "Happening in actuality" , "'Genuine, actual (4)'" .)