Percolate vs Undefined - What's the difference?

As a verb percolate

is to pass a liquid through a porous substance; to filter.

is (rare) a liquid that has been percolated.

lacking a definition or value.

To pass a liquid through a porous substance; to filter.

To drain or seep through a porous substance.

Water percolates through sand.

To make (coffee) in a percolator.

I'll percolate some coffee.

(figuratively) To spread slowly or gradually; to slowly become noticed or realised.

Reports on the pitiful state of many prisons have finally percolated through to the Home Office, which has promised to look into the situation.

Through media reports it percolated to the surface that the police investigation was profoundly flawed.

(en noun)

(rare) A liquid that has been percolated.

(wikipedia undefined) (-)

Lacking a definition or value.

(mathematics, computing) That does not have a meaning and is thus not assigned an interpretation.

The result of division by zero is undefined .

* defined