Ultimate origin (4)
I believe the answer is:
root
(Other definitions for root that I've seen before include "Origin; carrot perhaps" , "grub" , "radical" , "essential nature" , "Lowest part of plant" .)
I believe the answer is:
root
(Other definitions for root that I've seen before include "Origin; carrot perhaps" , "grub" , "radical" , "essential nature" , "Lowest part of plant" .)