定める
さだめる · sadameru · JLPT N1 · verb-ichidan
to decide
📜 定 = roof over a 'lid'; 定める = put a stake down and settle it, decide firmly
定 (じょう/てい) is built from 宀 (roof) over 疋 (foot/stop). Something stopped and fixed in place is settled, so 定める means to fix a decision firmly.
定 — roof 宀 + 正 (correct/upright, phonetic)
Originally written with 宀 (roof) over 正 (upright/correct), suggesting a household settled and orderly under its roof. Over time 正 simplified to 㐬-like form at the bottom, and the meaning shifted from 'settled home' to the broader senses of 'fix, stable, decide.'