One who, or that which, filters. "(Tissues) act as percolators."
2.
A type of coffee pot in which the heated water is driven by its boiling action up above a porous canister of coffee held above the level of the water in the pot, and then filters (percolates) back through the coffee thus extracting its essence.
3.
(Pharmacy) An apparatus for producing an extract from a drug by percolation.
... timbers were rotting away. Evidence of profit could have been found in the successive transformations the old hulk kept undergoing. First curtains went up on the stateroom windows, and if you looked inside, you saw new coverlets of down, and white sheets. A coffee percolator began to shine like polished gold on the counter. The shelter outside the door grew longer and longer, with more tables and better ones. A dozen hens or more began to cluck about over the white sand, bossed by a wicked rooster with a tenor voice who was more than a match ... — Mayflower (Flor de mayo) • Vicente Blasco Ibanez
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