nelson (n.)

type of wrestling hold, 1875, apparently from a proper or surname, but no one now knows whose.

Presently, Stubbs, the more skilful as well as the more powerful of the twain, seizes the luckless Jumper in a terrible gripe, known to the initiated as the Full Nelson. ["Lancashire Recreations," in Chambers's Journal, April 24, 1875]

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Definitions of nelson from WordNet
nelson (n.)
any of several wrestling holds in which an arm is passed under the opponent's arm from behind and the hand exerts pressure on the back of the neck;
Nelson (n.)
English admiral who defeated the French fleets of Napoleon but was mortally wounded at Trafalgar (1758-1805);
Synonyms: Horatio Nelson / Viscount Nelson / Admiral Nelson / Lord Nelson