The Hebrew name of the shofar blast made of nine short notes is teruah.
Teruah is one of the principal shofar sounds used on Rosh Hashanah. In common modern practice, it is produced as a rapid sequence of short, staccato notes, traditionally counted as nine. The word appears in the Torah in connection with the sacred observances of the seventh month, but the Torah does not spell out the exact musical form.
Rabbinic interpretation therefore discusses how teruah should sound. One related blast, shevarim, consists of three broken or wavering notes and is often described as resembling sighing. Teruah is more commonly characterized as a quick, trembling or alarm-like series. Because of uncertainty over the ancient form, Jewish law developed several blast patterns.
A standard sequence places teruah between two long tekiah blasts: tekiah-teruah-tekiah. Other sequences use shevarim or combine shevarim and teruah. The familiar total of at least 30 required sounds reflects these patterns, while many communities hear 100 or more sounds during Rosh Hashanah services.