tê-lō͘茶滷

yellow-brown substance on teaware

yellow-brown substance on teaware (usually after long use); tea stain

English Wiktionary, “茶滷” (CC BY-SA 4.0) — https://en.wiktionary.org/wiki/%E8%8C%B6%E6%BB%B7 · confidence: Medium (Wiktionary)