Sardine and pilchard are common names for various species of small, oily forage fish in the herring suborder Clupeoidei.[2] The term 'sardine' was first used in English during the early 15th century; a somewhat dubious etymology says it comes from the Italian island of Sardinia, around which sardines were once supposedly abundant.[3][4][5]
The terms 'sardine' and 'pilchard' are not precise, and what is meant depends on the region. The United Kingdom's Sea Fish Industry Authority, for example, classifies sardines as young pilchards.[6] One criterion suggests fish shorter in length than 15 cm (6 in) are sardines, and larger fish are pilchards.[7]
The FAO/WHO Codex standard for canned sardines cites 21 species that may be classed as sardines.[8] FishBase, a database of information about fish, calls at least six species pilchards, over a dozen just sardines, and many more with the two basic names qualified by various adjectives.