smelt

Any small anadromous fish of the family Osmeridae, found in the Atlantic and Pacific Oceans and in lakes in North America and northern part of Europe.

A fool; a simpleton.

These direct Men, they are no Men of fashion, Talk what you will, this is a very Smelt

Production of metal, especially iron, from ore in a process that involves heating and chemical reduction of metal compounds into purified metal.

Any of the various liquids or semi-molten solids produced and used during the course of such production.

1982, Raymond E. Kirk and Donald F. Othmer, Encyclopedia of Chemical Technology, Wiley, →ISBN, page 405, The green liquor, ie, [sic] the solution obtained on dissolving the smelt, contains an insoluble residue called dregs, which gives it a dark green appearance.

1996, Arthur J. Wilson, The Living Rock: The Story of Metals Since Earliest Time and Their Impact on Civilization, When the smelt was complete the crucible could be lifted out and the metal poured directly into the moulds, thus avoiding the need to break it up and remelt […]

To produce metal, especially iron, from ore in a process that involves heating and chemical reduction of metal compounds into purified metal.