Stopping is a phonological process in which a child substitutes a stop consonant (like /p, b, t, d, k, g/) for a fricative or affricate sound, which has continuous airflow (such as /s, z, f, v, ʃ, θ, ʤ/). This means the child “stops” the airflow that would be required for the target sound – for example, saying “tun” for “sun,” “doo” for “zoo,” or “tee” for “see.” In typical speech development, stopping is observed as children learn more difficult sounds, with different fricatives mastered at different ages. If a child continues to use stopping beyond these age ranges, it is considered a phonological impairment; the child’s speech may sound less intelligible, and speech therapy is often warranted to teach the correct production of the fricative or affricate sounds.
Barbara Dodd et al., “Phonological development: a normative study of British English-speaking children,” Clinical Linguistics & Phonetics 17, no. 8 (2003).
John E. Bernthal, Nicholas W. Bankson, and Peter Flipsen, Articulation and Phonological Disorders: Speech Sound Disorders in Children, 8th ed. (Boston: Pearson, 2017).
