Plants in this genus are shrubs or bushes with simple leaves and tube-shaped flowers with the petals forming two "lips" - the upper one with two lobes and the lower one with three.

Plants in the genus Hemigenia are shrubs or bushes with simple leaves which are arranged either in opposite pairs or in whorls.

[3] Plants in this genus can be distinguished from those in the similar and closely related Hemiandra by their less strongly odoriferous leaves and from Prostanthera, Microcorys and Westringia by technical differences in their stamens.

The genus Hemigenia was first formally described in 1810 by Robert Brown and the description was published in Prodromus Florae Novae Hollandiae.

[1][4] The genus name is derived from the Ancient Greek words hemi[5]: 392  and genias meaning "a beard"[5]: 365  referring to a part of the anthers.