a stone used as a base on which a building is constructed (often referred to the masonry, concrete works at the basement); a foundation stone.

(fig.) the fundamental work, plan or groundwork done for a project organisation, system, theory, etc.

that which is walked on, pressed or crushed with the feat trodden; a trampled thing.

that which has lost freshness or is withered, faded, etc.

the act or an instance of treading; a trampling.

the kitchen waste water.