The genus name Equilabium means ‘equal lips’ from aequus, meaning ‘even, level or equal’, and labia, meaning ‘lip’, referring to the upper and lower lips of the corolla being of roughly equal length. The specific epithet laxiflorus comes from Latin and means ‘loose-flowered’, referring to the lax arrangement of the inflorescence. This species was previously placed in the genus Plectranthus, the name meaning ‘spurflower’, derived from the Greek plektron, meaning ‘spur’ and anthos, which means ‘flower’; referring to the spur that is found at the base of the corolla tube of the type species for the genus, P. fruticosus. 

This species was moved into the genus Equilabium by Mwany, Paton and Culham in 2018 after molecular studies on Plectranthus and closely related genera by Paton et al show that the old definition of the genus Plectranthus did not have a single common ancestor, and that it contained two distinct clades separate from Plectranthus. The one clade including the type species of the former genus Coleus, which led to the re-instatement of the genus Coleus, and the other that is now recognized as the new genus Equilabium, with E. laxiflorum the designated type species for the genus; and a new, smaller Plectranthus was redefined. 

There are 42 species of Equilabium currently recognized, most of them occur in tropical Africa with 2 species in India. They are perennial or annual herbs or soft-wooded shrubs, sometimes succulent, usually aromatic, with simple, opposite leaves; thyrsoid inflorescence; funnel-shaped, 2-lipped, 5-lobed calyx; strongly 2-lipped, 5-lobed corolla, the upper lip ascending or erect, lower lip horizontal, hooded, enclosing the stamens; the corolla tube narrow, sigmoid (s-shaped), parallel-sided at base, widening towards the mouth (shaped like a Dutchman’s pipe or wooden tobacco pipe); fruit an ovoid nutlet, usually mucilaginous.
Three species occur in South Africa:
Equilabium dolomiticum (= Plectranthus dolomiticus), dolomite dutch-pipe-sage (Eng.); dolomiet-kromsteelpypsalie (Afr.)
Equilabium petiolare (= Plectranthus petiolaris), pink dutch-pipe-sage (Eng.); kromsteelpypsalie. (Afr.)
and Equilabium laxiflorum.

The new genus Equilabium can be distinguished from Coleus because the upper and lower lips of the corolla are equal, and in Coleus the upper lip is shorter than the lower. Also, in Equilabium, the pedicel attaches symmetrically, in the centre of the base of the pedicel, not asymmetrically as it does in Coleus. This latter character is the same as for Plectranthus, but Equilabium differs from Plectranthus in having a strongly to shallowly sigmoid corolla tube with parallel sides at the base whereas Plectranthus has a straight or downward curved corolla tube that usually has a swelling at the base.

This species was first collected at the Mzimvubu River near Port St Johns in 1832, by Johann Drège. It was introduced to Kirstenbosch National Botanical Garden in 1920 by Carnegie from Pietermaritzburg.