Allergic (6)
I believe the answer is:
averse
'allergic' is the definition.
(thesaurus)
This is the entire clue.
(Other definitions for averse that I've seen before include "Disinclined or reluctant" , "Disinclined, maybe to hard work" , "Disinclined - sounds like a poem" , "Not in favour of" , "Disinclined, loath" .)