American Heritage Dictionary
Century Dictionary
(6)
GNU Webster's 1913
(1)
WordNet
Elsewhere on the web
All the stuff' that we drive out we throw away, except about six inches on the top where the gold lies, so that the quantity of mullock, as we call it, or useless material hoisted out is very great.— The Lifeboat
Eh! but he do write bad; t' words is fair tum'lin' ower one anuther I was in a bit o' a mullock," Private James Akroyd's letter went on, "t' last time we were i' t' trenches; 'twern't mich to tell abaat, but 'twere hot while it lasted.— More Tales of the Ridings
Aw've had nowt to do wi' th' orderation o' this mullock, an' if ther's owt lost aw'll pay for it.— Yorksher Puddin' A Collection of the Most Popular Dialect Stories from the Pen of John Hartley
What this little thing is ne'er a body may tell, in my line of life--but look'th aristocratic The "mullock," as he called it, from his hands, and from the bed where it had lain so long, so crusted the little thing which he gave me, that I dipped it again in the swelling stream, and rubbed it with both hands, to make out what it was.— Erema — My Father's Sin
Used as a description of such a harsh region mullock: the tailings left after gold has been removed.— Children of the Bush

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