No, not the river (whose name is French, from Latin Mosa); this is an English dialect word I just ran across, with an unexpected etymology (French < Celtic) I thought I’d share. OED (updated December 2001):
Pronunciation: Brit. /mjuːs/ , /mjuːz/ , U.S. /mjuz/
Etymology: < Middle French muce, musse, mouce hiding place, secret place (1190 in Old French as muce; only from 1561 in spec. sense 1a; French regional (central and western) musse hiding place, hole in a hedge) < mucier, mucer to hide, conceal oneself (second half of the 12th cent.; compare Anglo-Norman muscier, muscer, mucier, etc.; also Italian (regional) mucciare, muccire to flee) < an unidentified reflex of the Celtic base of Early Irish múch smoke, Welsh mwg smoke, which in turn is related to the Germanic base of smoke v. Compare mitch v., muset n.1 Compare slightly earlier maze n.2 and discussion at that entry.
Recorded in Eng. Dial. Dict. s.v. in very widespread English regional use.
Now Brit. regional.
a. A gap in a fence or hedge through which hares, rabbits, etc., pass, esp. as a means of escape; (also) a man-made track or tunnel for leading hares, rabbits, etc., into a trap. Cf. run n.2 12a.
1523 J. Skelton Goodly Garlande of Laurell 1384 He wrate of a muse [1568 mows] throw a mud wall; How a do cam trippyng in at the rere warde.
1575 G. Gascoigne Noble Arte Venerie lix. 164 She..will all the daye long holde the same wayes..and passe through the same muses untill hir death or escape.
1623 T. Scott High-waies of God 55 A Hare started before Greyhounds will haue her accustomed way and muse, or die for it.
1754 W. Cowper Epist. to R. Lloyd 52 The virtuoso..The gilded butterfly pursues O’er hedge and ditch, through gaps and mews.
1756 Gentleman’s Mag. 26 180 The most effectual method of destroying hares is by laying snares..in the muishes of hedges, dykes, and other fences.
1812 W. B. Daniel Rural Sports (new ed.) I. 587 The Tipe or trap..consists of a large pit or Cistern, covered with a floor, with a small trap door, nicely balanced, near its centre, into which the rabbits are led by a narrow Meuse.
1821 Blackwood’s Edinb. Mag. 8 531 It is doubted whether the stoutest March hare will have sufficient vivacity to carry him to his muese.
1884 R. Lawson Upton-on-Severn Words & Phrases at Muse, Them Welshmen [sc. Welsh sheep]’d go through a rabbit run or a har’ muce.
1895 Athenæum 2 Mar. 285/3 In a stone-wall country you will not find a hare close to the lee side..because of the concentrated wind which whistles through every ‘meuse’.
1972 G. E. Evans & D. Thomson Leaping Hare vi. 75 An unusual method of catching hares..appears to have been extensively used by poachers in addition to the more common device of snaring or netting at the smiles or meuses.
2006 T. Williamson Archaeol. Rabbit Warrens vi. 54 (caption) A narrow wooden tunnel or muce runs through the wall and across the top of the pit; here there is a small trap-door in the tunnel floor.
†b. In extended use: a means of escape; (a device affording) a way out of a difficulty. Obs.
1528 J. Skelton Honorificatissimo: Replycacion agaynst Yong Scolers sig. Avi, Howe..ye had..deuyllysshely deuysed The people to seduce And chase them thorowe the muse Of your noughty counsell.
1606 W. Warner Continuance Albions Eng. xvi. cii. 404 When desprate Ruffins fraught with faults finde readily a Meuse.
1647 N. Bacon Hist. Disc. Govt. 184 In this Tragedy the Pope observing how the English Bishops had forsaken their Archbishop, espied a muse through which all the game of the Popedome might soon escape.
1858 R. S. Surtees Ask Mamma xxix. 116 The Major, after trying every meuse, and every twist, and every turn..was at length obliged to whip off.
†2. The form or lair of a hare; occas. with reference to other animals of the chase. Obs.
In 16th and 17th centuries freq. in proverbial sayings, as a hare without a meuse, every hare has its meuse, etc.
1585 S. Robson Choise of Change sig. Miii, Things very hard or not at all to be found. A hare without a muse…A whore without a skuse.
1598 G. Chapman tr. Homer Seauen Bks. Iliades vii. 123 As when a crew of gallantes watch, the wild muse of a bore.
1627 W. Hawkins Apollo Shroving v. iv. 86 Ludio The Nine Muses play at Nine-holes: euery Muse hath her hole. Thur. Yes, and euery Hare hath her Muse.
1788 W. Marshall Provincialisms E. Yorks. in Rural Econ. Yorks. II. 353 Smoot, a hare muce; or any small gap or hole in the bottom of a hedge.
1890 J. D. Robertson Gloss. Words County of Gloucester Mews, a hare’s form.
Note the odd form ‘lair of a hare,’ also new to me (it’s the OED’s sense 21); some citations:
a1300 Fragm. Pop. Sc. (Wright) 318 I-buyd as an hare Whan he in forme lyth.
c1386 Chaucer Shipman’s Tale 104 As in a fourme sitteth a wery hare.
1575 G. Gascoigne Noble Arte Venerie lviii. 161 When a Hare ryseth out of the forme.
1735 W. Somervile Chace ii. 38 In the dry crumbling Bank Their Forms they delve.
1845 C. Darwin Jrnl. (ed. 2) iii. 46 The Indians catch the Varying Hare by walking spirally round and round, it when on its form.
1952 R. Campbell tr. C. Baudelaire Poems 77 Whereon as in a fourm you would fill out And mould your hair.
I’m actually not sure the last one belongs here; it’s not at all clear to me what sense Campbell intended, since the line has little to do with Baudelaire’s French (“Qui, comme une guérite, enfermera tes charmes”). You can see the poem in the original with three translations here (William Aggeler and Lewis Piaget Shanks both render guérite accurately as “sentry-box”).
Addendum. It turns out I wrote about this word and its etymology less than three months ago. Sigh. At least it gets its own post here.