PURPOSE: Bound morphemes are challenging for children who are deaf and hard of hearing (DHH) to acquire and to use successfully. The challenge arises in part from limited access to spoken word forms as a result of reduced audibility during perception, but successful comprehension requires access to METHOD: Seventy-eight elementary school-age children who are DHH were tested on their perception and comprehension of four bound morphemes: third-person - RESULTS: Analyses both confirmed the reliability of the measures of perception and comprehension and revealed generally higher performance for perception over comprehension. Critically, correlations between perception and comprehension were mostly not significant. Secondary findings included that higher performance for one bound morpheme did not imply higher performance on others and a significant relationship between measures of vocabulary and performance on the bound morpheme tasks. CONCLUSIONS: The findings of the study highlight the importance of distinguishing between perception versus comprehension of morphological forms. Successful comprehension requires form-meaning mapping, whereas successful perception requires only acquisition of form. Both theoretical and practical implications of the mapping component of speech processing are discussed, including the value of providing programs of auditory training that are meaning-oriented in nature.