root, radical, head (pimple)
根 centers on the base or source of something: a plant's root, the fundamental part of a thing, or the core of a pimple. The radical sense extends this to the root-like role of a component in other characters.
根 combines 木 (tree) with 艮, which likely contributes the sound and the idea of a base or stopping point, suggesting the root of a tree.
A tree 木 with its roots spreading out like the shape 艮: the root is the foundation that anchors the tree.
For コン, imagine a cone-shaped root growing deep into the ground: cone -> コン, and the root anchors the tree.
roof
root (of a plant)
basis; grounds; foundation; reason; authority
root; source; origin
Shimane (prefecture)
daikon (variety of large white Oriental radish, Raphanus sativus var. longipinnatus)
willpower; guts; determination; grit; spirit
(mountain) ridge
root; basis; foundation
root; source; origin; cause
firmly rooted; deep-seated
eradication; extermination; rooting out; stamping out; getting rid of
foundation; root; basis; core; fundamentals
root; joint; base; crotch
patience; perseverance; persistence; tenacity; energy
root (of a plant)
hedge; fence
roots of grass; places hidden from sight
laying the groundwork; behind-the-scenes maneuvering; consensus-building process
groundless; entirely contrary to fact
root of an evil; source of a problem; source of trouble; cause of misfortune
to come from; to have roots in
inquisitively; pryingly; nosily; thoroughly; persistently; through-and-through
fundamental; basic