Isidore of Seville [7th century CE] (Etymologies, Book 12, 6:23): The bream (dentix) is named for the great number and size of its teeth (dens).. - [Barney, Lewis, et. al. translation]

Thomas of Cantimpré [circa 1200-1272 CE] (Liber de natura rerum, Fish 7.32): Dentrix or peagrus, as Isidore says, derives its name from the fact that it has hard teeth, large and many, with which it gnaws at oysters or harmless fish. These fishes signify those who rule with cruelty, and have many cruel servants, by whose service they creep into the prisons of the poor as into oysters, and into those who lead a harmless life by their labor. - [Badke translation/paraphrase]

Bartholomaeus Anglicus [13th century CE] (Liber de proprietatibus rerum, Book13.26): Fish that eate other fishes have strong teeth, as that manner Fish that Greekes call Phagion. Isidore saith, that that Fish hath so hard téeth, that he eateth Oysters in the Sea: and therefore he is called Dentrix, as it were a fish strongly toothed, and hath that name for greatnesse and strength of téeth - [Batman]