Second person in Paris coming in to block piece of information (5)
I believe the answer is:
datum
'piece of information' is the definition.
(I've seen this before)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for datum that I've seen before include "Little bit of information" , "Given piece of information" , "Basic fact" , "Single informative fact" , "Fact or stat" .)