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.
... where the river bends at the foot of the cataract, with considerable noise. I found myself in a sort of open-air parlor flanked by two tents; rustic seats under a canopy of maple boughs, hammocks, a percolator bubbling on a sheet-iron contrivance over the camp-fire coals, and, looking at me across a table, the girl. 'I beg your pardon,' I hurried to say. 'Don't be ... — The Rim of the Desert • Ada Woodruff Anderson
... noon!" gasped Mrs. Van Zandt, in horror. "What on earth was old lady Morgan thinking of? Mr. Hard, if you'll throw some more wood into the stove, I'll put on the percolator and run down to the dining-room for some sandwiches." She ran off in one direction, while Scott drove the team in another, leaving ... — Across the Mesa • Jarvis Hall