noun /dò/
D (alternative), d (alternative)
Definitions
  1. The syllable used to represent the low-tone and its diacritic (`)
    Ẹ bá mi fàmì sí "pàtàkì" pà-tà-kì dò-dò-dò Help me tone mark "pàtàkì" pà-tà-kì low-tone, low-tone, low-tone
Etymology
From do used in solfège to represent the first tonic of a major scale.
Source: Wiktionary · etymology 1, where this word is spelled “do”. Reference: en-do-yo-noun-g6sWO8up