E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
of beef. Corruption of Naitch-bone, i.e. the haunch-bone (Latin, nates, a haunch or buttock).
Similarly, an apron is a corruption of a napperon; an adder is a corruption of a nadder (Old Eng., nddre). In other words, we have reversed the order; thus a newt is an ewt; a nag is an ög (Danish). Latin, eq[uus], a horse.