"deep mud, bog, marsh, swampland," c. 1300, from a Scandinavian source such as Old Norse myrr "bog, swamp," from Proto-Germanic *miuzja- (source of Old English mos "bog, marsh"), from PIE *meus- "damp" (see moss).
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.
updated on January 27, 2019