Accurate perception of emotional (facial) expressions is an essential social skill. It is currently debated whether emotion categorization in infancy emerges in a "broad-to-narrow" pattern and the degree to which language influences this process. We used an habituation paradigm to explore (a) whether 14- and 18-month-old infants perceive different facial expressions (anger, sad, disgust) as belonging to a superordinate category of negative valence and (b) how verbal labels influence emotion category formation. Results indicated that infants "did not" spontaneously form a superordinate category of negative valence (Experiments 1 and 3). However, when a novel label ("toma") was added to each event during habituation trials (Experiments 2 and 4), infants formed this superordinate valance category when habituated to disgust and sad expressions (but not when habituated to anger and sadness). These labeling effects were obtained with two stimuli sets (Radboud Face Database and NimStim), even when controlling for the presence of teeth in the expressions. The results indicate that infants, at 14 and 18 months of age, show limited superordinate categorization based on the valence of different negative facial expressions. Specifically, infants only form this abstract emotion category when labels were provided, and the labeling effect depends on which emotions are presented during habituation. These findings have important implications for developmental theories of emotion.