Initial letters clue? (8)
I believe the answer is:
signpost
'clue?' is the definition.
(I've seen this before)
'initial letters' is the wordplay.
'initial' becomes 'sign' (I can't explain this - if you can you should give a lot more credence to this answer).
'letters' becomes 'post' (letters in the mail or post).
'sign'+'post'='SIGNPOST'
Can you help me to learn more?
(Other definitions for signpost that I've seen before include "Direction indicator" , "pointer along the way" , "Route indicator" , "Indication of direction" , "Wayside indicator" .)