megrim Lepidorhombus whiffiagonis, a flatfish of the W. Mediterranean and E. Atlantic. It is fished from relatively deep waters and attains a maximum length of 60 cm (24"); so, although its market length is much less, it is a sizeable fish. It enjoys moderate esteem in Spain but is generally regarded as unexciting, tending to be dry, and best fried with plenty of fat. The phrase ‘to have the megrims’ has nothing at all to do with the fish, that word being a variation of migraine. The dictionaries profess ignorance of the derivation of the fish-name.