Grace note 花音 (音乐)
A grace note is a kind of music notation used to denote several kinds of musical ornaments, usually printed smaller to indicate that it is melodically and harmonically nonessential. When occurring by itself, a single grace note normally indicates the intention of either an appoggiatura or an acciaccatura. When they occur in groups, grace notes can be interpreted to indicate any of several different classes of ornamentation, depending on interpretation.