Chiloglottis trilabra was first formally described in 1883 by Robert D. FitzGerald and the description was published in Journal of Botany, British and Foreign from a specimen obtained on Mount York in the Blue Mountains. The specific epithet (trilabra) is derived from the Latin prefix tri- meaning three: and labra meaning lip.: The type specimen happened to be an aberrant form having two extra labellums in place of two lateral sepals.