c. 1200, scalden, "to be very hot;" also "to affect (someone) painfully by short exposure to hot liquid or steam," from Old North French escalder "to scald, to scorch" (Old French eschalder "heat, boil up, bubble," Modern French échauder), from Late Latin excaldare "bathe in hot water" (source also of Spanish escaldar, Italian scaldare "heat with hot water"), from Latin ex "out, out of" (see ex-) + calidus "hot" (from PIE root *kele- (1) "warm"). Related: Scalded; scalding.
"[T]he word entered at an early date into the Scandinavian languages" [OED]. The noun is c. 1600, from the verb, "burn or injury to the skin by hot liquid or steam."
I'm a poor underdog
But tonight I will bark
With the great Overdog
That romps through the dark.
[from "Canis Major," Robert Frost, 1928]
the Australian dog, of wolf-like appearance and very fierce, 1789, Native Australian name, from Dharruk (language formerly spoken in the area of Sydney) /din-go/ "tame dog," though the English used it to describe wild Australian dogs. Bushmen continue to call the animal by the Dharruk term /warrigal/ "wild dog." Plural dingoes.