nutter

noun3

1. •
   (informal, offensive) An eccentric, insane, crazy or reckless person.

   • That bird who's hanging' out with you is mad like cat piss / Like bread and jam, or a knife going with butter / Face it son, your missus is a nutter! — 2005
2. •
   A person who gathers nuts.
3. •
   (no longer used) nut butter

   • Nut Butter (Table Nutter) is also recommended. — 1907