An adverb is a part of speech that has not yet been thoroughly investigated in isiNdebele. In this study, we conduct an in-depth investigation of isiNdebele adverbs, morphologically, and semantically. Adverbs are classified into three subcategories namely: locative adverbs, adverbs of time, and adverbs of manner. The study followed a qualitative research approach and a corpus-based method of data collection. Relevant sentences containing adverbs from isiNdebele secondary sources were extracted and analysed using content analysis. The basic linguistic theory was used as a theoretical framework. Morphologically, the analysis shows that isiNdebele adverbs are formed differently from different parts of speech. Locative adverbs are predominantly derived from nouns and pronouns through the process of affixation. In the case of nouns, locative adverbs are formed by attaching locative morphemes such as ku-, e-, -eni, or -ini to name a few. While, locative prefix ku-, ki- and kwa- are used to form the same adverbs that are derived from pronouns. Also, locative adverbs are formed by the prefixnge- which normally occurs before the velar consonant -k. Adverbs of time are formed from abstract nouns of time by replacing the original prefixes with the prefix e-. Some proper nouns are also used to create adverbs of time by prefixing ng-.However, other isiNdebele adverbs of time are not derived from other parts of speech but are still recognised as adverbs by language speakers. Lastly, the adverbs of manner are specifically derived from adjectives and relatives through the process of morpheme addition. Semantically, all subcategories of isiNdebele adverbs do not alter the original meaning of the words, but rather they modify the part of speech after the necessary morphological processes are applied. Keywords: Locative adverbs, Adverbs of time, Adverbs of manner, Morpho-semantic, Morphemes NWU CORONA VIRUS: http://www.nwu.ac.za/coronavirus/ Vrywaringsklousule / Disclaimer: http://www.nwu.ac.za/it/gov-man/disclaimer.html