Two-year-olds readily learn multiple labels for the same basic-level category.

2 basic frameworks for lexical principles have been proposed (Golinkoff, Mervis, & Hirsh-Pasek; Markman). In many types of situations, these frameworks make the same predictions regarding 2-year-olds' interpretation of novel terms. However, the predictions diverge in some cases. 3 experiments were conducted to address 1 such situation: the case in which the child hears a novel term but already knows a label for each of the objects present. Results of all 3 studies converged on the same outcome: The new term was most likely to be treated as a second basic-level name for the category to which the object belonged. Analyses of individual patterns of responding revealed that, of the 58 subjects, 50 made more basic-level responses than part responses, 1 made equal numbers of basic-level and part responses, and 7 made more part responses than basic-level responses. Implications of these findings for models of early lexical development are discussed.