thiat-tīng鐵定

ironclad

ironclad; fixed; unalterable; certainly; surely

adverb

English Wiktionary, “鐵定” (CC BY-SA 4.0) — https://en.wiktionary.org/wiki/%E9%90%B5%E5%AE%9A · confidence: Medium (Wiktionary, Hokkien)