Bother with false lashes (6)
I believe the answer is:
'bother' is the definition.
(I know that bother can be written as hassle)
'false lashes' is the wordplay.
'false' indicates an anagram.
'lashes' with letters rearranged gives 'HASSLE'.
'with' acts as a link.
(Other definitions for hassle that I've seen before include "Nuisance, bother" , "Les has (anag) - a great deal of trouble" , "Bother, fuss" , "Modern word for bother and annoyance" , "Bug" .)