The Vietnamese word for neck is
cổ

Translations for neck and their definitions

cổ	©
1. n. neck
cổ tay - a wrist
cổ chân - an ankle
cổ chai - a bottleneck
2. adj. ancient; "old"; compare cũ
Ai Cập cổ - Ancient Egypt
3. adj. antique; "old"; compare cũ
đồ cổ - antiques
4. pron. (southern Vietnam) she/her, that young adult woman

Pronunciation