song, ballad
唄 centers on vocal music: a song or ballad, often with a traditional or narrative feel.
唄 combines 口 (mouth) with 貝, which likely contributes the sound バイ. The character is used for songs or ballads, especially in a Buddhist chanting context.
A mouth 口 singing beside a shell 貝, like a bard singing ballads by the seashore.
For バイ, imagine buying a ballad from a street singer: buy -> バイ, and the mouth 口 sings the song.
kouta; traditional ballad accompanied by shamisen
long epic song with shamisen accompaniment (developed in Edo in the early 17th century)
Ringo no uta (1946 song; the first post-war hit song)
song sung behind the scenes
work song
work song
uta-sanshin (variety of Okinawan folk music)
singer in a nagauta performance
(style of) folk song
lullaby
traditional Okinawan folk music
putting on a brave front; pretending one doesn't care; song of a convict on their way to prison
song praising the virtues of the Buddha
Bon Festival dance song
short love song (popular in late Edo period)
song sung behind the scenes
Singin' in the Rain (1952 film and song)