We’ve trimmed down the American Orchid Society’s reference info down to this handy cheat sheet for you.
The first word is the name of the genus (plural: genera). It is usually printed in italics with a capital letter. Botanists abbreviate generic names with the first letter while horticulturists often use short abbreviations, such as Phal. for Phalaenopsis.
Within each genus there may be dozens, if not hundreds, of variations. Taxonomists give them individual names called specific epithets (these usually begin with a lower-case letter and are also in italics). They may indicate place of origin, the person who found the orchid, a characteristic of the orchid or honor an individual.
Some orchid species may exhibit certain characteristics with additional variation which taxonomists recognize by assigning a subspecies, varietal or form name. These begin with a lower-case letter, are in italics and are the third name in sequence.
The Names of Hybrids
When a hybrid is made, the breeder, or his or her representative, assigns a grex or group name that applies to all of the hybrid progeny.
Some plants with exceptionally fine flowers have been observed and assigned cultivar names to distinguish them. Cultivar names may be applied to hybrids as well as orchid species. They begin with a capital letter, are in Roman type and set within single quotation marks. All derivatives of a cultivar will be genetically identical and possess the same cultivar name, so hobbyists know exactly what to expect from a plant they purchase bearing this name.
Extra letters may follow the plants' names, which indicates an award. These may be given to both species and hybrids. The letters before the slash are an abbreviation for the award; AM is an Award of Merit, HCC a Highly Commended Certificate. The letters following the slash indicate the association that bestowed the award, such as the American Orchid Society (AOS).