Whole note

In music, a whole note (American) or semibreve (British) is a note represented by a hollow oval note head and no note stem. Its length is equal to four beats in 4
4 time, that is the whole 4
4 measure (or bar). Most other notes are fractions of the whole note (e.g., half notes and quarter notes are played for one half and one quarter the duration of the whole note, respectively).

The symbol is first found in music notation from the late thirteenth century, and its British name derives from the semibrevis of mensural notation, which is the origin of the British name. The whole note and whole rest may also be used in music of free rhythm, such as Anglican chant, to denote a whole measure.

A whole note (American) or semibreve (British) is a musical note represented by a hollow oval note head—like a half note (or minim)—and no note stem (see Figure 1). Its length is equal to four beats in 4
4 time, that is the whole 4
4 measure (or bar). Most other notes are fractions of the whole note. Half notes last for one half the duration of the whole note, quarter notes (or crotchets) last for one quarter the duration, and a double whole note (or breve, hence the British name semibreve) lasts twice as long as a whole note.

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