Any of several terrestrial orchids of the genus Chiloglottis (and formerly Caladenia), which are native to Australasia and have flowers that resemble small insects.
Origin
Early 20th century.
Definition of ant orchid in US English:
ant orchid
noun
Any of several terrestrial orchids of the genus Chiloglottis (and formerly Caladenia), which are native to Australasia and have flowers that resemble small insects.