This study investigated a child's development of the concept that a word is a unit used to express meaning. Thirty children, selected at random from grades one through six, were chosen from a school where no exclusive method of teaching reading was used. Each child participated in two tasks. First, a list of nouns was presented in written form and the child rated 24 words as known and 24 words as unknown. A word-choice task followed, in which the child explained how chosen words went together for him or her. Children gave significantly more semantic responses if either the question word or the choice word was known and if the word was in oral form rather than written. The research data suggest that children who are reading in school tasks would benefit from greater understanding and use of metalanguage. (MAI)