Stuttering and stammering

A stutter or stammer was a speech impediment involving involuntary repetition of sounds, but also pauses, the use of incorrect words, or excessive corrections.

Causes
While it could occur randomly or constantly in sufferers, inherent stuttering could become noticeable or exacerbated in social situations, such as when speaking to large groups; and in states of nervousness.

People normally without the impediment might stutter when surprised, shocked, or frightened  or when nervous. Severe cold could also cause an effect similar to stuttering, via chattering teeth.

Stuttering and stammering could also be induced by the cursed philter of stammering and stuttering (though a jester bard might turn this to their advantage)  or as a potential side-effect in the user of a wand of wonder IV, when it produced an effect similar to the philter.

The magical condition called mindshadow madness had as its initial stage a brief period of stuttering or babbling nonsense words.

Effects
By inhibiting speech, a stutter or stammer might disrupt diplomacy, the uttering of verbal components to spells, or the recitation of a magical scroll. Others might react poorly to them, by thinking what they said was nonsense, or getting impatient with them. Overall, a stutterer might speak much more slowly than would be normal.

History
In the, Giogioni Wyvernspur was shocked into a bout of stuttering when he discovered a red dragon devouring his horse, Daisyeye. Mistinarperadnacles Hai Draco suggested he try to relax. Shortly after, he stuttered again when King Azoun IV ordered him to do an impression of him. Vangerdahast attributed his response to shock.

Known Stutterers

 * Khalid, had a recurring strong stutter;
 * Chanczlatha Luruin, had a recurring stammer;
 * Clacker, a pech turned into a hook horror with a recurring stutter;
 * Delitar the Slow, named for his slow, stuttering speech;
 * Ellis Adarbrent, stuttered when nervous;
 * Kalib bin Jabir, stuttered in social situations;
 * Ko La Ko, stuttered when speaking to large groups;
 * Maddgoth, had a strong stammer; and
 * Shulgi, a vampire with a stutter.

Trivia
The year 314 DR was called the Year of the Stammering Apprentice.

Kobold wild mages had a tendency to stutter, as well as suffer random spasms and seizures in addition to spontaneous displays of magic.