Turn against stranger at last on phone (8)
I believe the answer is:
alienate
'turn' is the definition.
(thesaurus)
'against stranger at last on phone' is the wordplay.
'against' becomes 'alie' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'stranger' indicates an anagram.
'last' suggests the final letters.
The last letters of 'on phone' are 'ne'.
'at'+'ne'='atne'
'atne' with letters rearranged gives 'nate'.
'alie'+'nate'='ALIENATE'
Can you help me to learn more?
(Other definitions for alienate that I've seen before include "Turn away from" , "Cause someone to feel estranged" , "Eat alien in order to make hostile" , "Cause a friend to become hostile" , "cut off" .)