tasteless
tasteless; flavorless
English Wiktionary, “無味無素” (CC BY-SA 4.0) — https://en.wiktionary.org/wiki/%E7%84%A1%E5%91%B3%E7%84%A1%E7%B4%A0 · confidence: High (Wiktionary, PH/Quanzhou/Jinjiang)