This plant species is a member of Crassulaceae family also known as stonecrops or plakkies, which is predominately a group of succulents, with thick and fleshy leaves that the plant uses to store water and food. The genus name Crassula is derived from the Latin adjective crassus meaning ‘thick’ or ‘fat’, referring to the thick succulent leaves typical of the plant species under this genus.

Crassula swaziensis was first described in 1897 from a type specimen that was collected in 1895 by a German-South African botanist named Selmar Schönland. He named it swaziensis meaning ‘of Swaziland’ because it was found in what is now Eswatini (formerly Swaziland). In 1902 it was reclassified as Crassula argyrophylla. In 1929, Schönland himself reclassified this plant species suggesting it was not a separate species to Crassula argyrophylla but a variant and it became Crassula argyrophylla var. swaziensis.

Because it is a variable species, numerous forms and varieties were named between 1929 and 1975, such as Crassula swaziensis subsp. swaziensis var. gurnensis, Crassula swaziensis subsp. swaziensis var. gurnensis. forma brevipilosa, Crassula swaziensis subsp. swaziensis var. gurnensis. forma gurnensis, Crassula swaziensis subsp. swaziensis var. swaziensis, Crassula swaziensis subsp. swaziensis var. swaziensis forma argyrophylla , and Crassula swaziensis subsp. swaziensis var. swaziensis forma swaziensis. More studies in nature and of herbarium specimens were conducted and the conclusion reached was that the other varieties and forms linked to Crassula swaziensis were not valid, and they were then grouped together to form a single species. Because Crassula swaziensis was the first official name given in 1897, that name remained. Today, Crassula swaziensis is the accepted name, and the other names such as Crassula argyrophylla, Crassula argyrophylla var. swaziensis and Crassula swaziensis var. swaziensis are all considered as synonyms.