1. Stammer, stutter mean to speak with some form of difficulty. Stammer, the general term, suggests a speech disfluency that results in broken or inarticulate sounds and sometimes in complete stoppage of speech; it may be temporary, caused by sudden excitement, confusion, embarrassment, or other emotion, or it may be persistent and require speech therapy for its correction. Stutter, the parallel term preferred in technical usage, designates a broad range of speech production disturbances that produce spasmodic interruptions of the speech rhythm, repetitions, or prolongations of sounds or syllables: The child's stutter was no mere stammer of embarrassment.

Did you mean tampering?