Native: a genus that contains about 330 species of orchids; widespread from northern Mexico, the Caribbean, and some parts of South Florida to South America; usually occur in seasonally dry areas
Type: most species are epiphytes, although some are lithophytes or terrestrials
Size: flowers are not large, but this is more than compensated for in most species by the great numbers of flowers produced on long, often branched inflorescences
Colors: some have long racemes with small flowers and a dominant lip that are mostly golden yellow with or without reddish-brown barring, but some are brown or yellowish-brown; other species have white and pink blooms, while some even have startling, deep red colors
Growth pattern: sympodial with each new growth arising from the previous growth
Pseudobulb: have pseudobulbs with one to three leaves; there are several basal bracts at the base of the pseudobulbs
Roots: roots of most species are fine and numerous
Known for: name is derived from Greek word "onkos", meaning "swelling" referring to the callus at the lower lip; known as 'spray orchids' among some florists; most common variety is often referred to as Dancing Lady
History: first described by Olof Swartz in 1800

The petals are often ruffled on the edges, as is the labellum. The labellum is enormous, partially blocking the small petals and sepals.

A complicated callus on the labellum distinguishes the Oncidium and can be used to separate the taxa. The presence of column wings is another Oncidium characteristic.