• WordNet 3.6
    • n obbligato a part of the score that must be performed without change or omission
    • n obbligato a persistent but subordinate motif
    • ***
Century Dictionary and Cyclopedia
    • obbligato In music, indispensable; so important that it cannot be omitted: especially used of accompaniments of independent value.
    • n obbligato An accompaniment, whether for a solo or a concerted instrument, which is of independent importance; especially, an instrumental solo accompanying a vocal piece.
    • n obbligato Also spelled obligato.
    • ***
Chambers's Twentieth Century Dictionary
    • adj Obbligato ob-li-gä′to that cannot be done without
    • n Obbligato a musical accompaniment, itself of independent importance, esp. that of a single instrument to a vocal piece.—Also Obliga′to
    • ***


In literature:

The music served as obbligato for the mighty diapason of men's voices; the thousands talked as they waited.
"The Landloper" by Holman Day
The "morning hate" of the German family with ragtime obbligato must be a terrible thing!
"Mr. Punch's History of the Great War" by Punch
And ever and again pealed distantly into the chorus the flute obbligato of an emotional coyote down on the flat.
"Somewhere in Red Gap" by Harry Leon Wilson
Among other songs, one with an effective obbligato for the violoncello deserves special praise.
"Contemporary American Composers" by Rupert Hughes
Then there were more solos and duets, with obbligatos for the violin.
"The Martian" by George Du Maurier
The men in charge had heard the thunder of the oncoming racers, with its ominous obbligato of screams and shooting.
"The Bartlett Mystery" by Louis Tracy
The lady with the shoulders became a vibrating obbligato.
"The Blower of Bubbles" by Arthur Beverley Baxter

In news:

The concert opened with a brilliant performance of a not-so- brilliant work, Ernest Bloch's entertaining Concerto Grosso for String Orchestra and Piano Obbligato.