Highly suspicious airman lacking papers (8)
I believe the answer is:
paranoid
'highly suspicious' is the definition.
(paranoid means extremely suspicious)
'airman lacking papers' is the wordplay.
'airman' becomes 'para' (paratrouper).
'lacking' becomes 'no' (eg lacking money means with no money).
'papers' becomes 'ID' (identification papers).
'para'+'no'+'id'='PARANOID'
(Other definitions for paranoid that I've seen before include "Paid Nora to have delusions?" , "one given to suspicion" , "Excessively suspicious" , "Suffering delusions; road pain (anag.)" , "Irrationally obsessed by fear etc" .)