the.com/fundamental
The bottom turtle in the stack, the one everything else is standing on.
means Forming the necessary base or core of something, so basic that removing it collapses the whole thing.
from From Latin fundamentum, foundation, from fundare, to lay a base, from fundus, bottom — the same root that gives us funds and the very floor of your bank account.
Physics termFundamental forces number just four, holding reality together.
Music meaningThe fundamental is a note's lowest, defining frequency.
Same rootProfound literally means toward the bottom.