Salmonids

Different people use the term "salmonid" in slightly different ways.

Sometimes the term is used as a shortened form of the word "Salmonidae," the biological family to which salmon and trout belong. The members of this family include whitefish, cisco, and char as well as salmon and trout.

At other times the term is used to refer just to the more "trout-like" and "salmon-like" members of the family and excludes the whitefish and cisco.

Any organism can be categorized by its position in the Linnean Binomial System of nomenclature. Here is the position of the Brook Trout, Salvelinus fontinalis, in this hierarchy:
 

kingdom:	Animalia	all animals
phylum:	Chordata	with notochord
	Vertebrata	with backbones
subphylum:	Gnathostoma	with jaws
superclass:	Pisces	fish
class:	Osteichthyes	bony fish
subclass:	Actinopterygii	ray fined fishes
superorder:	Teleostei	modern teleost scales
order:	Salmoniformes	pike pickrel blackfish smelts whitefish salmon trout
suborder:	Salmonoidei	smelts whitefish salmon trout
family:	Salmonidae	Coregonus - cisco, whitefish Oncorhynchus - pacific salmon Prosopium - whitefish Salmo - trout, atlantic salmon Salvelinus - see below Stenodus - inconnu
genus:	Salvelinus	various char dolly varden brook trout lake trout
species:	fontinalis	brook trout