Building emotion categories: Children use a process of elimination when they encounter novel expressions

•Preschoolers can use a process of elimination to learn about novel facial expressions.•Children linked a novel expression and label in two different study designs.•Prolonged expression recognition development may be related to language acquisition.

Recent research has indicated that language provides an important contribution to adults’ conceptions of emotional expressions and their associated categories, but how language influences children’s expression category acquisition has yet to be explored. Across two studies, we provide evidence that when preschoolers (2–4 years) encounter a novel label, they use a process of elimination to match it with its expected expression. Children successfully used a process of elimination to match a single expression to one of several labels (Study 1) and to match a single label to one of several expressions (Study 2). These data highlight one possible mechanism that children may use to learn about the expressions they encounter and may shed light on the ways in which children’s expression categories are constructed.