Dimensional adjectives: factors affecting children's ability to compare objects using novel words.

A series of 3 studies tested the hypothesis that children's difficulty acquiring dimensional adjectives, such as big, little, tall, and short, is a consequence of how these words are used by adults. Three- and 4-year-olds were asked to compare pairs of objects drawn from a novel stimulus series using real dimension words (taller and shorter; Study 1) and novel dimension words (maller and borger; Studies 1-3). Characteristics of testing, including the presence or absence of a categorization task, were manipulated. Findings indicated that children easily acquired novel dimension words when they were used in a strictly comparative fashion but had difficulty when also exposed to the categorical form of usage. It is concluded that having to learn both categorical and comparative meanings at once may impede acquisition of dimensional adjectives.