Tendency to have security number as means of increasing access? (8)
I believe the answer is:
driftpin
'means of increasing access?' is the definition.
The definition suggests a singular noun which matches the answer.
'tendency to have security number' is the wordplay.
'tendency' becomes 'drift' (drift is a kind of tendency).
'to have' means one lot of letters go next to another.
'security number' becomes 'pin' (a PIN number - personal identification number).
'drift'+'pin'='DRIFTPIN'
'as' is the link.
Can you help me to learn more?
(Another definition for driftpin that I've seen is " that makes holes bigger".)