The use and understanding of ordinal terms (e.g., "first" and "second") is a developmental milestone that has been relatively unexplored in the preschool age range. In the present study, 4- and 5-year-olds watched as a reward was placed in one of three train cars labeled by the experimenter with an ordinal (e.g., "first" car), color (e.g., "brown" car), or generic label (e.g., "that" car). Results revealed that 4-year-olds actually had more difficulty retrieving the reward once occluded under identical tunnels when they were provided with ordinal labels compared to color and generic labels. Search performance improved with age and showed dramatic growth in the ordinal-label condition from 4 to 5 years of age. Results are discussed with regard to children's ability to use verbal labels of developing conceptual knowledge (i.e., linked to ordinality) to guide behavior.