Runner runs left across island, alongside verge (7)
I believe the answer is:
tendril
'runner' is the definition.
(thesaurus)
'runs left across island alongside verge' is the wordplay.
'runs' becomes 'r' (cricket abbreviation).
'left across island' becomes 'il' (I can't explain this - if you can you should believe this answer much more).
'alongside' says to put letters next to each other.
'verge' becomes 'tend' (to verge towards something is to tend towards it).
'r'+'il'='ril'
'ril' put after 'tend' is 'TENDRIL'.
Can you help me to learn more?
(Other definitions for tendril that I've seen before include "Natural thread climbing plants produce to attach to a support" , "Coiling shoot of climbing plant" , "Clinging part of a plant" , "Thread-like part by which climbing plant clings" , "Climbing plant's means of support" .)