Maroon filament (6)
I believe the answer is:
strand
I believe this is a double definition.
'maroon' is the first definition.
(as in stranding or marooning someone somewhere)
'filament' is the second definition.
(synonyms)
(Other definitions for strand that I've seen before include "Thread; leave in lurch" , "Shore; single fibre" , "Single hair; drive ashore" , "Thread - London street" , "Drive aground; thread" .)