a variety of lake trout, Salvelinus namaycush siscowet, inhabiting the deeper waters of Lake Superior.
Origin: 1840–50, Americanism; shortening of Ojibwa pe⋅mite⋅wiskawe⋅t fish with oily flesh (deriv. of pimite⋅w- oil + -iskawe⋅ (of fish) to have flesh (of the specified type), or deriv. of another word with the same final element)