Name associated with Facebook article, police onto that (4)
I believe the answer is:
meta
'name' is the definition.
(I know that Meta is a name)
'facebook article police onto that' is the wordplay.
I cannot really understand how this works, but
'article' could be 'a' (the indefinite article in English) and 'a' is found in the answer.
'police' could be 'met' (London Metropolitan Police) and 'met' is found in the answer.
This accounts for all the letters.
This explanation may well be incorrect...
'associated with' acts as a link.
Can you help me to learn more?
(Another definition for meta that I've seen is " Prefix meaning behind or beyond something".)