Common name

In biology, a common name of a taxon or organism is a name that is based on the normal language of everyday life. It is often contrasted with the scientific name for the same organism, which is often based in Latin. Common names can be used frequently, but that is not always the case.
In chemistry, IUPAC defines a common name as one that, although it unambiguously defines a chemical, does not follow the current systematic naming convention, such as acetone, systematically 2-propanone, while a vernacular name describes one used in a lab, trade or industry that does not unambiguously describe a single chemical, such as copper sulfate, which may refer to either copper sulfate or copper sulfate.
Sometimes common names are created by authorities on one particular subject, in an attempt to make it possible for members of the general public to be able to refer to one particular species of organism without needing to be able to memorise or pronounce the scientific name. Creating an "official" list of common names can also be an attempt to standardize the use of common names, which can sometimes vary a great deal between one part of a country and another, as well as between one country and another country, even where the same language is spoken in both places.

Use as part of folk taxonomy

A common name intrinsically plays a part in a classification of objects, typically an incomplete and informal classification, in which some names are degenerate examples in that they are unique and lack reference to any other name, as is the case with say, ginkgo, okapi, and ratel. Folk taxonomy, which is a classification of objects using common names, has no formal rules and need not be consistent or logical in its assignment of names, so that say, not all flies are called flies and not every animal called a fly is indeed a fly. In contrast, scientific or biological nomenclature is a global system that attempts to denote particular organisms or taxa uniquely and definitively, on the assumption that such organisms or taxa are well-defined and generally also have well-defined interrelationships; accordingly the ICZN has formal rules for biological nomenclature and convenes periodic international meetings to further that purpose.

Common names and the binomial system

The form of scientific names for organisms, called binomial nomenclature, is superficially similar to the noun-adjective form of vernacular names or common names which were used by non-modern cultures. A collective name such as owl was made more precise by the addition of an adjective such as screech. Linnaeus himself published a flora of his homeland Sweden, Flora Svecica, and in this, he recorded the Swedish common names, region by region, as well as the scientific names. The Swedish common names were all binomials ; the vernacular binomial system thus preceded his scientific binomial system.
Linnaean authority William T. Stearn said:

Geographic range of use

The geographic range over which a particularly common name is used varies; some common names have a very local application, while others are virtually universal within a particular language. Some such names even apply across ranges of languages; the word for cat, for instance, is easily recognizable in most Germanic and many Romance languages. Many vernacular names, however, are restricted to a single country and colloquial names to local districts.
Some languages also have more than one common name for the same animal. For example, in Irish, there are many terms that are considered outdated but still well-known for their somewhat humorous and poetic descriptions of animals.

Scientific name	English name	Irish terms w/ literal translations of the poetic terms
Vulpes vulpes	Red fox	Madra rua or sionnach
Lutra lutra	Otter	Madra uisce or dobharchú
Canis lupus	Wolf	Mac Tíre or faolchú
Chiroptera	Bats	Sciathán leathair or ialtóg

Constraints and problems

Common names are used in the writings of both professionals and laymen. Lay people sometimes object to the use of scientific names over common names, but the use of scientific names can be defended, as it is in these remarks from a book on marine fish:

Because common names often have a very local distribution, the same fish in a single area may have several common names.
Because of ignorance of relevant biological facts among the lay public, a single species of fish may be called by several common names, because individuals in the species differ in appearance depending on their maturity, gender, or can vary in appearance as a morphological response to their natural surroundings, i.e. ecophenotypic variation.
In contrast to common names, formal taxonomic names imply biological relationships between similarly named creatures.
Because of incidental events, contact with other languages, or simple confusion, common names in a given region will sometimes change with time.
In a book that lists over 1200 species of fishes more than half have no widely recognised common name; they either are too nondescript or too rarely seen to have earned any widely accepted common name.
Conversely, a single common name often applies to multiple species of fishes. The lay public might simply not recognise or care about subtle differences in appearance between only very distantly related species.
Many species that are rare, or lack economic importance, do not have a common name.
Coining common names

In scientific binomial nomenclature, names commonly are derived from classical or modern Latin or Greek or Latinised forms of vernacular words or coinages; such names generally are difficult for laymen to learn, remember, and pronounce and so, in such books as field guides, biologists commonly publish lists of coined common names. Many examples of such common names simply are attempts to translate the scientific name into English or some other vernacular. Such translation may be confusing in itself, or confusingly inaccurate, for example, gratiosus does not mean "gracile" and gracilis does not mean "graceful".
The practice of coining common names has long been discouraged; de Candolle's Laws of Botanical Nomenclature, 1868, the non-binding recommendations that form the basis of the modern International Code of Nomenclature for algae, fungi, and plants contains the following:
Various bodies and the authors of many technical and semi-technical books do not simply adapt existing common names for various organisms; they try to coin comprehensive, useful, authoritative, and standardised lists of new names. The purpose typically is:

to create names from scratch where no common names exist
to impose a particular choice of name where there is more than one common name
to improve existing common names
to replace them with names that conform more to the relatedness of the organisms

Other attempts to reconcile differences between widely separated regions, traditions, and languages, by arbitrarily imposing nomenclature, often reflect narrow perspectives and have unfortunate outcomes. For example, members of the genus Burhinus occur in Australia, Southern Africa, Eurasia, and South America. A recent trend in field manuals and bird lists is to use the name "thick-knee" for members of the genus. This, in spite of the fact that the majority of the species occur in non-English-speaking regions and have various common names, not always English. For example, "Dikkop" is the centuries-old South African vernacular name for their two local species: Burhinus capensis is the Cape dikkop ; Burhinus vermiculatus is the "water dikkop". The thick joints in question are not even, in fact, the birds' knees, but the intertarsal joints—in lay terms the ankles. Furthermore, not all species in the genus have "thick knees", so the thickness of the "knees" of some species is not of clearly descriptive significance. The family Burhinidae has members that have various common names even in English, including "stone curlews", so the choice of the name "thick-knees" is not easy to defend but is a clear illustration of the hazards of the facile coinage of terminology.

Lists that include common names

Lists of general interest

;Plants

;Animals

;Plants and animals

Invasive species
Collective nouns

For collective nouns for various subjects, see a list of collective nouns.

Official lists

Some organizations have created official lists of common names, or guidelines for creating common names, hoping to standardize the use of common names.
For example, the Australian Fish Names List or AFNS was compiled through a process involving work by taxonomic and seafood industry experts, drafted using the CAAB taxon management system of the CSIRO, and including input through public and industry consultations by the Australian Fish Names Committee. The AFNS has been an official Australian Standard since July 2007 and has existed in draft form since 2001.
Seafood Services Australia serve as the Secretariat for the AFNC. SSA is an accredited Standards Australia Standards Development
The Entomological Society of America maintains a database of official common names of insects, and proposals for new entries must be submitted and reviewed by a formal committee before being added to the listing.
Efforts to standardize English names for the amphibians and reptiles of North America began in the mid-1950s. The dynamic nature of taxonomy necessitates periodical updates and changes in the nomenclature of both scientific and common names. The Society for the [Study of Amphibians and Reptiles] published an updated list in 1978, largely following the previous established examples, and subsequently published eight revised editions ending in 2017. More recently the SSAR switched to an online version with a searchable database. Standardized names for the amphibians and reptiles of Mexico in Spanish and English were first published in 1994, with a revised and updated list published in 2008.
A set of guidelines for the creation of English names for birds was published in The Auk in 1978. It gave rise to Birds of the World: Recommended English Names and its Spanish and French companions.
The Academy of the Hebrew Language publish from time to time short dictionaries of common name in Hebrew for species that occur in Israel or surrounding countries e.g. for Reptilia in 1938, Osteichthyes in 2012, and Odonata in 2015.