F98: Other behavioural and emotional disorders with onset usually occurring in childhood and adolescence

F98.5: Stuttering [stammering]

When you speak, you keep repeating specific sounds, words or parts of words. You may also draw out particular sounds or parts of words too much. When you speak, you may also pause or hesitate in saying words. There is a noticeable tension, then, as you speak or pause. Your normal speech is disrupted as a result. The person is usually aware that their speech is not working normally. The person may avoid speaking much as a result. Under stress, the stuttering may get worse and the speech less easy to understand.

When a person stutters, they may also make particular movements at the same time, or freeze.