Children’s processing and comprehension of metonymy have received little attention in the developmental literature, which has mainly focused on children’s acquisition of metaphor abilities. However, it has been found that metonymy production and comprehension precede metaphor production and comprehension (Falkum et al., 2017; Nerlich et al., 1999; Pérez-Hernández & Duvignau, 2016; Runblad & Annaz, 2010). Nerlich et al. (1999) suggest that metonymic relations are exploited in overextensions produced by children up to age 2;5 and call these “compelled metonymic overextensions”. At this very early age, a child’s vocabulary is still relatively small, and this compels them to extend already known words to cope with their increasing communicative needs. These overextensions are, however, in most cases not random, as some type of associative relation (e.g., cause–effect, object–act, container–content, etc.) between the concepts referred to can be identified. This study focuses on the metonymic relations exploited by 18 Afrikaans-speaking infants and toddlers (between the ages of 0;6 and 2;0) in their early overextensions. The metonymic relations as described by Norrick (1981) as well as Radden and Kövecses (1999) are employed in the analysis. A total of 207 out of 1371 one-word utterances were identified as compelled metonymic overextensions and 11 types of metonymic relations could be identified as underlying these utterances. This study illustrates that the metonymic relations identified in such young children’s early language provide insight and understanding into how they categorise and associate various concepts with each other.