Yodeling is a unique form of singing that involves a rapid change in pitch between low and high notes. Synonyms for the term yodeled include warbled, trilled, quavered, sang out, vocalized, crooned, and yipped. Each of these terms denotes a musical expression that is either high-pitched, rapid, or a combination of the two. Warbling is characterized by vibrato and is commonly used in the transition between low and high vocal ranges. Trilling refers to a fluctuation in pitch, similar to yodeling. Quavering is a wavering of pitch, while singing out is more forceful and can be of any pitch. The term yipped has a more animalistic connotation and is often used when referring to a sudden burst of sound.