General English


  • A round, non-oily sea water fish, Gadus morrhua, from the northern oceans up to 40 kg in weight with a white flaky flesh and a grey green skin. Used to be cheap and common in the northern hemisphere. dried and salted it is a major item in international trade as a protein source.


  • adjective excellent. The word has been used in this sense by schoolchildren since the mid-1990s.


  • acronym forchemical oxygen demand
    (written as COD)

General Science

  • noun the amount of oxygen taken up by organic matter in water used as a measurement of the amount of organic matter in sewage.

Origin & History of “cod”

like most fish-names, the origins of cod are obscure. It has been suggested, not all that convincingly, that it comes from another word cod (OE), now obsolete, which meant broadly ‘pouch’ – the idea being that the fish supposedly has a ‘baglike’ appearance. among the specific applications of this other cod, which was of Germanic origin, were ‘seedcase’ (which survived into the twentieth century in the archaic compound peascod ‘pea pod’) and ‘scrotum’. By transference the latter came to mean ‘testicles’, whence codpiece, a 15th- to 17th-century garment somewhat analogous to the jockstrap. The cuttle of cuttlefish comes from the same source.