Sibilance is a figure of speech and a literary device that creates a hissing sound within a group of words through the repetition of "s" sounds. It is a type of alliteration that is often used in poetry and song lyrics to create a musical element and emphasize words that resonate with the main ideas or themes of the work. Sibilants are fricative consonants that are made by directing a stream of air with the tongue towards the teeth, resulting in a higher amplitude and pitch. Examples of sibilants include the consonants at the beginning of the English words sip, zip, ship, and genre.

Sibilants are louder than their non-sibilant counterparts, and most of their acoustic energy occurs at higher frequencies than non-sibilant fricatives, usually around 8,000 Hz. All sibilants are coronal consonants, which means they are made with the tip or front part of the tongue. However, there is a great deal of variety among sibilants as to tongue shape, point of contact on the tongue, and point of contact on the upper side of the mouth.

Sibilance is a useful tool for both poets and writers, helping inject atmosphere and feeling into a written work. The use of sibilant sounds is meant to mesmerize or lull the observer, and it can be communicated in many different ways in linguistics. Some scholars disagree on whether or not some sounds qualify as sibilance, but universally agreed-upon sibilant sounds include the preface S or double S, and Ts.