This article outlines the challenges relating to the lemmatization of the lexical items which are either polysemous or homonymous, as experienced during the compilation of the Sesotho sa Leboa–English Bilingual Dictionary. These problems can be ascribed to a lack of objectivity result-ing from an inadequate knowledge regarding the etymological relationships of the meanings of some lexical items which are subsequently misclassified as either homonyms or polysemous words. This often causes improper lexical entries in dictionaries, i.e. polysemous words may be lemma-tized as homonyms and vice versa. To unambiguously distinguish between lexical items which are either homonyms or polyse-mous words, lexicographers should in this regard consider the criteria suggested by scholars: — In accordance with the relatedness/unrelatedness criterion, the lexicographer will need to determine the extent to which the lexical items are related before entering them in the dic-tionary. — The etymological criterion will help the lexicographer to determine the relatedness of the lexical items for inclusion in the dictionary according to their historical connection. Using these criteria to lemmatize a lexical item properly in the dictionary, the lexicographer will be required to determine whether a lexical item can be regarded as one word with more than one meaning (a polysemous word), or as two different lexical items which have the same spelling (homonyms). To make this distinction, the lexicographer will need to research the historical back-ground of the lexical item. Even though these criteria are important aids for distinguishing polysemy and homonymy, the problem of subjectivity is not altogether removed since the criteria do not specify the level or degree of relatedness/unrelatedness at which the lexical item(s) can be said to be polysemous or homonymous.