"a heap of dung," early 14c., from dung (n.) + hill (n.).
Entries linking to dunghill
dung n.
late Old English dung "manure, decayed matter used to fertilize soil," from Proto-Germanic *dungō (source also of Old Frisian and Old Saxon dung "manure;" Old High German tunga "manuring," tung "underground room covered with manure;" German Dung; Old Norse dyngja "heap of manure, women's apartment;" Swedish dynga "dung, muck;" Danish dynge "heap, mass, pile"), perhaps from a PIE *dhengh- "covering" (source also of Lithuanian dengti "to cover," Old Irish dingim "I press").
The word recalls the ancient Germanic custom (reported by Tacitus) of covering underground shelters with manure to keep in warmth in winter. The meaning "animal excrement," whether used as fertilizer or not, is from late 13c.
It appears that the whole body of journeymen tailors is divided into two classes, denominated Flints and Dungs: the former work by the day and receive all equal wages; the latter work generally by the piece ["The Annual Register for the Year 1824," London, 1825].
Dung beetle, common name of the beetles which roll up balls of dung," is attested by 1630s. In colloquial American English, tumble-bug. An Old English word for it was tordwifel "turd weevil."
hill n.
Old English hyll "hill," from Proto-Germanic *hulni- (source also of Middle Dutch hille, Low German hull "hill," Old Norse hallr "stone," Gothic hallus "rock," Old Norse holmr "islet in a bay," Old English holm "rising land, island"), from PIE root *kel- (2) "to be prominent; hill." Formerly including mountains.
In Great Britain heights under 2,000 feet are generally called hills; 'mountain' being confined to the greater elevations of the Lake District, of North Wales, and of the Scottish Highlands; but, in India, ranges of 5,000 and even 10,000 feet are commonly called 'hills,' in contrast with the Himalaya Mountains, many peaks of which rise beyond 20,000 feet. [OED]
The term mountain is very loosely used. It commonly means any unusual elevation. In New England and central New York, elevations of from one to two thousand feet are called hills, but on the plains of Texas, a hill of a few hundred feet is called a mountain. [Ralph S. Tarr, "Elementary Geology," Macmillan, 1903]
Despite the differences in defining mountain systems, Penck (1896), Supan (1911) and Obst (1914) agreed that the distinction between hills, mountains, and mountain systems according to areal extent or height is not a suitable classification. ["Geographic Information Science and Mountain Geomorphology," 2004]
Figurative phrase over the hill "past one's prime" is recorded by 1950. Expression old as the hills is recorded by 1819, perhaps echoing Job xv.7. Earlier form old as the hills and the valleys is attested by 1808:
And this is no "new morality." It is morality as old as the hills and the valleys. It is a morality which must be adopted; or, we must confess that there are certain political evils greater than that of seeing one's country conquered. [Cobbett's Weekly Political Register, Feb. 6, 1808]
Cobbett's also had, on April 11, 1818:
However, thus it always is: "those whom God intends to destroy, he first makes foolish," which is a saying as old as the hills between Everly and Marlborough.