Flutter-tonguing is a wind instrument tonguing technique in which performers flutter their tongue to make a characteristic "FrrrrFrrrrr" sound. The effect varies according to the instrument and at what volume it is played, ranging from cooing sounds on a recorder to an effect similar to the growls used by jazz musicians.
In sheet music, the technique is usually indicated with the standard tremolo markings on a note alongside a text instruction to flutter the note. The German marking "Flatterzunge" is often abbreviated to "Flz." or "Flt.". The Italian "frullato" is sometimes abbreviated to "frull". In English, the most common indication is "f.t." Other markings that composers have used to indicate flutter tonguing include: coupe de lange roulé, en roulant la langue, tremolo dental, tremolo avec la langue, tremolo roulé, vibrata linguale, vibrando, and colpo di lingua among others.However, simply writing (3-line) tremolo marks on all rhythmic values without other indication is most generally accepted.
One of the earliest uses of flutter-tonguing was by Pyotr Ilyich Tchaikovsky in his ballet The Nutcracker. In the opening of the final act, Tchaikovsky makes the flutes flutter-tongue to depict the cascading river of rose-oil seen as Clara and the Nutcracker are welcomed to the kingdom of Confiturembourg: he named the effect frulato, as did the flautist who first introduced him to the technique, Alexander Khimichenko.
The effect has since been called for in many classical compositions, where it is most often used on flutes, recorders, bassoons, trumpets, and trombones, but can be used on other brass and woodwind instruments as well. The technique became quite common in the 20th century, notably occurring in the music of Schoenberg and Shostakovich, where it can have a nightmarish or sarcastic effect, or conversely by Benjamin Britten who uses the effect on the recorder in Noye's Fludde to imitate the cooing of a dove, or in Curlew River on solo flute to suggest both the mental state of the Madwoman and also the curlews she identifies with.