Scottish National Dictionary (1700–)
SLUSH, n., v. Also sluish. Sc. usages:
I. n. 1. A wet marshy place, a puddle, quagmire (Sc. 1710 T. Ruddiman Gl. to Douglas Aeneis); thin muddy liquid, “any dirty liquid, dregs” (Cld. 1880 Jam.). Hence slushy, -ie, adj., of drink or the like: weak, wishy-washy, insipid; of crops: waterlogged, “broken-down, lodged, . . . heavy and coarse-strawed, but not firm” (Ork. 1929 Marw.; Sh., Ork., Cai. 1970). Deriv. slushrie, sloppy food, used attrib. in 1847 quot.
Peb. 1715 A. Pennecuik Tweeddale 23:
Tweed, from its first head, runs down to a place upon the high way called Tweed's Slush. Edb. 1839 W. McDowall Poems 117:
Can slushy tea ere be compared Wi' cogs o' brose? Rxb. 1847 J. Halliday Rustic Bard 144:
The cook o' slushrie . . . stews. Gsw. 1898 D. Willox Poems 255:
The brewster may exhaust his skill In perfecting his slushy yill. s.Sc. 1900 Border Mag. (May) 88:
There's a lot o' bog holes and slush in the narrow opening.
2. A slovenly, untidy person, a slut; a menial worker, a drudge, “skivvy” (Sc. 1825 Jam.). Hence slushy, adj., slatternly, slovenly, dirty at work or in appearance (Ork. 1929 Marw.; Sh., Ork., Cai. 1970).
Rxb. 1847 J. Halliday Rustic Bard 182:
To make yer wife a slush, yer bairns a scorn? Sh. 1900 Shetland News (13 Jan.):
Ye shürely a' notic'd what a slush I wis.
3. A heavy, slothful way of walking, a slovenly carriage, a shuffling gait (Rxb. 1923 Watson W.-B., sluish); one who walks in this way, a heavy, awkward person (Id.).
4. A speech peculiarity in which the lateral l  is used in place of the normal s  (Slg., m.Lth., Lnk. 1970).
Edb. 1964 :
He spoke wi a slush — e.g. Shome shpeakersh shay sho.
II. v. 1. To splash, squelch, to splutter, to slobber. Deriv. slusher, n., a painter's term for a large whitewash brush or similar large brush used for applying paint in large quantities or a wholesale way (Fif. 1952).
Abd. 1714 R. Smith Poems (1853) 82:
With slushing and souching, Each one his Cutty reeks. Sc. 1838 M. Scott T. Cringle's Log xii.:
Like so many pigs slushing at the same trough.
2. To work in a messy, untidy or careless way (Ork. 1929 Marw.; Sh., Ork., Cai. 1970). Hence slushit, slovenly in dress or manner (Sh. 1866 Edm. Gl.), slushidness, n., sloppiness, want of neatness and order.
Sh. 1900 Shetland News (13 Jan.):
I saw nae slushidness aboot dee. I tink doo shew da neetest ane 'at wis dere.
3. To wade messily through wet mud or the like, to walk with shuffling or dragging footsteps. Vbl.n. slushing. Used fig. in 1864 quot.
Sc. 1864 Carlyle Frederick xvi. viii.:
Slushings hither and thither in the muddy tide-currents. Rxb. 1923 Watson W.-B.:
Jock cam' sluishin' alang the cassa. Dmb. 1931 A. J. Cronin Hatter's Castle iii. i.:
You'll see great big cows slushing about.
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"Slush n., v.". Dictionary of the Scots Language. 2004. Scottish Language Dictionaries Ltd. Accessed 19 Feb 2019 <http://www.dsl.ac.uk/entry/snd/slush>
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