a note that alternates rapidly with another note a semitone above it
the articulation of a consonant (especially the consonant `r') with a rapid flutter of the tongue against the palate or uvula; "he pronounced his R's with a distinct trill"
pronounce with a trill, of the phoneme `r'; "Some speakers trill their r's"
the filtration of a liquid for extraction or purification
the act of making coffee in a percolator
the slow passage of a liquid through a filtering medium; "the percolation of rainwater through the soil"; "the infiltration of seawater through the lava"