Articulation Delay/Disorder is the atypical production of speech sounds characterized by sound substitutions, omissions, additions, or distortions that may interfere with speech intelligibility.
Children with this disorder may have trouble controlling their rate of speech.
Or they may lag behind playmates in learning to make speech sounds. For
example, a child at age 6 will say "wabbit" instead of "rabbit" and "thwim"
for "swim." Developmental articulation disorders are common. They appear in at
least 10 percent of children younger than age 8. Fortunately, articulation
disorders can often be successfully treated with speech therapy.