"of or pertaining to the sole of the foot," 1706, from Latin plantaris "pertaining to the sole of the foot," from planta "sole of the foot" (from nasalized form of PIE root *plat- "to spread").
popular name of a German-American Anabaptist sect, 1756, from (Pennsylvania) German Tunker, from tunken, dunken "to dip, soak" (see dunk (v.)). So called because they practice adult baptism by triple immersion. The proper name is Brethren.
As an adjective in English from 1650s, in reference to words, containing or measuring a foot and a half. The meaning "sesquipedalian word" (1830) is from Latin sesquipedalia verba "words a foot-and-a-half long," in Horace's "Ars Poetica," nicely illustrating the thing he describes. Related: Sesquipedalianism.
"gout in the foot" (hence gout, generally), late 14c., from Latin podagra, from Greek podagra "gout in the feet," from pod-, stem of pous "foot" (from PIE root *ped- "foot") + agra "a catching, seizure," related to agrein "to take, seize."