From Proto-Tai *cramꟲ.
Cognate with Thai ถ้ำ (tâm), Lao ຖ້ຳ (tham), Northern Thai ᨳ᩶ᩣᩴ, Khün ᨳ᩶ᩣᩴ, Lü ᦏᧄᧉ (ṫham²), Shan ထမ်ႈ (thām), Tai Nüa ᥗᥛᥲ (thàm), Ahom 𑜌𑜪 (thaṃ), Zhuang gamj.
ꪖꪾ꫁ (thẳm)