Where does “hình thang” come from?

hình thang (Vietnamese) comes from Vietnamese thẳng, from Chinese 湯, from Proto-Sino-Tibetan r-la(w)ŋ — steam; hot.

hình thang (Vietnamese): trapezoid/trapezium

Definitions

  1. trapezoid/trapezium

Ancestry of “hình thang”, step by step

hình thang traces back through two separate lines of ancestry.

via Vietnamese thẳng

StepLanguageWordMeaning
1Vietnamesethẳngstraight
2Chinese湯—
3Proto-Sino-Tibetanr-la(w)ŋsteam; hot

via Vietnamese hình

StepLanguageWordMeaning
1Vietnamesehìnhimage; a figure or a silhouette; a photo; a...
2Chinese型—
Every word from Proto-Sino-Tibetan r-la(w)ŋ →Every word from Chinese 湯 →Every word from Vietnamese thẳng →