Recent research on children's word learning has led to a paradox. Although
word learning appears to be a deep source of insight into conceptual knowle
dge for children, preschoolers often categorize objects on the basis of sha
llow perceptual features such as shape. The current studies seek to resolve
this discrepancy. We suggest that comparing multiple instances of a catego
ry enables children to extract deeper relational commonalities among catego
ry members. We examine 4-year-olds' categorization behaviors when asked to
select a match for a target object (e.g., an apple) between a perceptually
similar, out-of-kind object (e.g., a balloon) and a perceptually different
category match (e.g., a banana). Children who learn a novel word as a label
for multiple instances of the category are more likely to select the categ
ory match over the perceptual match. Children who learn a label for only on
e instance are equally likely to select either alternative. This effect is
present even when individual target instances are more perceptually similar
to the perceptual choice than to the category choice. We conclude that str
uctural alignment processes may be: important in the development of categor
y understanding.