la (1)EnglishOxford Dictionary of Englishla1 /lɑː / (also lah) ▸ noun 1 Music (in tonic sol-fa) the sixth note of a major scale. ▪ the note A in the fixed-doh system. 2 a wordless syllable sung in the refrain of a song or as a replacement for the lyrics: they all join in with the la-la-las a girl absent-mindedly sings ‘la la la’ over a gorgeous French disco-pop backing. – ORIGIN Middle English: representing (as an arbitrary name for the note) the first syllable of Latin labii, taken from a Latin hymn (see solmization).