The isiXhosa colloquial names of 86 taxa of South African land mammals recorded in three mammalogical works and three isiXhoxa dictionaries are tabulated and discussed. This reveals several ambiguities, discrepancies, inconsistencies and uncertainties, as well those species and groups of species for which the names are not in doubt. Resolving the doubts would benefit the administration of environmental law, and would assist fieldworkers doing mammal/ biodiversity surveys in isiXhosa-speaking areas. Improving the accuracy and consistency of information provided in the standard works would also be beneficial. Such a resolution would best be done by zoologists working with lexicographers. Consequently, the paper is written with both zoologist and lexicographer in mind, and information is given that may be common knowledge to one but not the other.