1. Any plant of the orchis family, often remarkable for brilliancy of color or grotesqueness (bizarre, outlandish) of form, in some cases resembling various insects and other animals. Orchids are often epiphytes that grow upon trees without taking nourishment from them. They usually have their stems swollen into fleshy pseudobulbs that store water and mineral nutrients available from rain, dew, and dust; many exotic species are now cultivated for their beauty.
2. Any member of the family Orchidaceae; plants that have complex, specialized irregular flowers usually with only one or two stamens.
3. A well defined family of monocotyledons comprising 15 000 to 30 000 species in 600 to 800 genera of strongly mycotrophic terrestrial or often epiphytic herbs; cosmopolitan in distribution but most abundant and diverse in tropical forests; characterized by numerous, often bizarre specializations for pollination by particular species of insects; usually green and commonly crassulacean acid metabolism; producing from a thousand to several millions of tiny seeds with a minute undifferentiated embryo that requires association with an appropriate fungus for successful germination

Crassulacean acid metabolism refers to the fixation of carbon dioxide in the dark into organic acids which are used in photosynthesis by day.

Orchids were once called "ballocks stones" (ballock’s-grass is an old name for various sorts of wild orchids), "dogstones", and similar names because their tubers (roots) resemble human testicles. The name "orchid" derives from orchis, the Greek for “testicle”. The Latin form orchis was taken by botanists of the 16th and 17th centuries as the basis for the plant’s scientific name.

Orchid came into English about 1845, borrowed from New Latin Orchideae, Orchidaceae, the plant’s family name, and was assigned by Linnaeus in 1751, from orchid-, erroneously assumed as the stem of Latin orchis.

The resemblance of orchid roots to “testicles” more than 2 000 years ago led to the mistaken belief that orchids possess aphrodisiac properties. The identity of the true male orchis of the Greeks and Romans has never been established. Mystery still surrounds this magic plant whose root was dissolved in goat’s milk by the ancients. One drink of this solution, wrote one incredulous historian, and a man could perform sex as many as 70 consecutive times.

Orchis is supposed to have been the main ingredient of satyrion, the love food of those lecherous satyrs of Greek mythology. The orchid, the Turkish orchis morio, the truffle, the mandrake, and several other plants have been credited with being the male orchis (aphrodisiac) of the ancients, but the true identity of satyrion is probably lost for all time; unless you count ™Viagra as its replacement.