The Vietnamese word for three is
ba

Translations for three and their definitions

ba	©
1. n. (chiefly southern Vietnam) father
2. adj. (southern Vietnam, of a sibling) secondborn
anh/chị ba - second eldest brother/sister
bác ba - second eldest brother/sister of one's parent
chú ba - secondborn younger brother of one's father
3. det. (colloquial) some, an indefinite quantity greater than one
Ba cái đó chả đáng quan tâm. - There's no need to be concerned about those.
4. n. (only in compounds) wave; ripple

Pronunciation