weakfish

Calque from Dutch weekvis, weekvisch (“weakfish”), equivalent to weak +‎ fish, because of its tender mouth.

weakfish (plural weakfishes or weakfish)

1. Any of several species of game fish, of the genus Cynoscion, found in North American waters.
   • 1962, International Oceanographic Foundation, Sea Secrets, Volumes 6-8, page 2084,

     Weakfishes have no adipose fin, such as fresh-water trouts possess: […] .

   • 1991, Michael R. Ross, Recreational Fisheries of Coastal New England, page 194,

     Larger fish tend to migrate farther north than smaller ones; thus, the New England weakfish fishery may possess a higher percentage of large individuals than is characteristic of the coastwide fishery. Weakfish tend to move about in schools of similar-sized individuals.

   • 2001, Salt Water Sportsman, "Inshore Salt Water Fishing: Learn from the Experts at Salt Water Magazine", [page 90],

     The weakfish is referred to as a gray trout from Maryland south, mainly to separate it from the spotted seatrout (p. 36), which is found in the southern portion of the weakfish’s range. Weakfish (Cynoscion regalis) look very much like a freshwater trout, although they exhibit few characteristics of this species.

   • 2009, Ken Schultz, Ken Schultz's Essentials of Fishing, page 73,

     The weakfish is also a member of the Sciaenidae family, and its name refers to the tender, easily torn membrane in the fish's mouth, not its fighting ability.

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