I used an inflected form of the transitive verb "to slather" while enjoying lunch with a woman from Japan today and stopped her in her linguistic tracks. I used it correctly -- to describe butter smeared thickly on toast -- but could not respond when she asked me from whence this interesting verb came? Etymologists to the front, please.

OED says Of obscure origin.

looking around a bit more, I was rewarded with this sidebar on the noun form of slather:

Daring hypothesis: English words for “mud”, “near-mud”, “dried-mud”, and “mud like” outnumber Eskimo words for “snow”, “near-snow”, etc. etc.

Can this be true? Let’s have a look! (GJV)
Sludge, muck, slush, rile, slut, slime, bog, stabble (mud made by footprints), marsh, swill, ooze, slip, morass, slunk (a muddy or marshy place), mere, pulk, swamp, cay, blash, baygall, quag, quagmire, sump, slosh, sludge, squash, wichert (white, chalky mud, Bucks.), sleech (mud deposited by a river), clart, fen, humus, slough, bauger, slabber, warp (a moist bed of alluvial sediment), mush, chaitia (dried mud), gumbo, slumgullion (a muddy deposit in a mining sluice, US), slop, wallow, squad (dial., soft mud), slurry (thin mud or cement), parafango (a mixture of mud and paraffin), sludder, stodge (thick, tenacious mud), quicksand, schlich, slake (mud left by the tide), soss (a slop, Sc), cloam (potter’s mud), sinkhole, gunk, goo, clay, slob[Ir], palus, mire, slather (thin mud, Yorks.), sewerage (street mud), adobe (dried mud), limus, silt, loam, smirch, clag (mud entangled with wool on sheep), and this is only a start. Source: OED2

Since lather functions in the same descriptive way (i.e...lather it on), perhaps the addition of the "S" is a colloquial exaggeration? Maybe even brought about by the contraction of the term "lots of lather"? I tend to use "slathered it on" or "slather it on" when I mean "coating it extra-heavily in a sloppy sort of way."

I agree that it seems very likely 'slather' comes from lather Whitman, especially considering the Old English meaning of lather, 'to cover with'. Maybe 'lather' has been combined with 's' because so many words with similar meanings start with 's', e.g. slap on, slop. A portmanteau? An odd onomatopoeic invention from lather? Either way it's is great sounding word.


aside: Any Aussies remember 'Slip,Slap,Slop'

I always suspected (without reason or support) that is was a portmanteau of 'spread' and 'lather,' or something similar. Probably goes back a long time.

Slather is a really good word when you want lots of something, like marmalade or jam on your toast ... if you're dealing with someone who tends to be mingy with the spread!

That said, how come we slather only onto flat things ... you don't slather hot fudge on ice cream but you can slather whipped cream on the cake ... or slather paint on a wall.

Glad you're back with us Father Steve ... all moved in and settled?

how come we slather only onto flat things

I feel that slathering involved a flat instrument used to spread the stuff, like a knife, for butter, or a putty knife, for polyfilla, and so on. Anyway, you don't use a knife to put hot fudge on ice cream. However, that might be just my interpretation! (mmm...getting hungry...)