flat worm-like animal, 1819, from Modern Latin (1776) noun use of fem. of Late Latin planarius, literally "on level ground" (here used to mean "flat"), from Latin planum, planus "flat, level, even, plain" (from PIE root *pele- (2) "flat; to spread"). Related: Planarian.

"to soil or wet by dragging in dirt or mud or from being rained upon," 1727, from be- + draggle "to drag or draw along damp ground or mud." Also in a similar sense were bedrabble (mid-15c.), bedaggle (1570s).

word-forming element meaning "level, flat, plane," from Latin plani-, from planus "flat, level" (from PIE root *pele- (2) "flat; to spread").

c. 1400, in figurative sense of "to involve in difficulties," from mire (n.). Literal sense of "to plunge or fix in mire, sink or stall in mud" is from 1550s; that of "to cover in mud or filth" is from c. 1500. Related: Mired; miring.

mid-15c., "state or quality of being flat," from flat (adj.) + -ness.

"low land covered wholly or partly by water, a marsh abounding in coarse vegetation," Old English fenn "mud, mire, dirt; fen, marsh, moor," from Proto-Germanic *fanja- "swamp, marsh" (source also of Old Saxon feni, Old Frisian fenne, Middle Dutch venne, Dutch veen, Old High German fenna, German Fenn "marsh," Old Norse fen, Gothic fani "mud"), from PIE *poino-, from root *pen- "swamp" (source also of Gaulish anam "water," Sanskrit pankah "bog, marsh, mud," Old Prussian pannean "swampland"). Italian and Spanish fango, Old French fanc, French fange "mud" are loan-words from Germanic. The native Latin word was limus or lutum.

"abounding with mud, swampy, boggy," late 14c., from mire (n.) + -y (2). Related: Miriness.

also flat-fish, 1710, from flat (adj.) + fish (n.). So called from the shape.

"horse that runs well in muddy conditions," 1903, from mud (n.).

1952, from snow (n.) + tire (n.). Earlier mud-and-snow tire (1948).