Several parts combine into one character.

全 is read as 入 (to enter) over 玉 (the 王-shape, jade) — possessing a flawless jade (玉) under a roof (入), hence "whole, complete, all." It points to a state fully provided, like an unblemished jade with nothing missing.

Korean hanja-sound "jeon": 全體 (jeonche, the whole), 完全 (wanjeon, complete), 安全 (anjeon, safety), 全部 (jeonbu, all), 全國 (jeon-guk, the whole country), 健全 (geonjeon, sound). It is the commonest character for "wholly, all."

Mandarin: quán, 2nd tone. 全部 (quánbù, all), 安全 (ānquán, safety), 完全 (wánquán, completely), 全国 (quánguó, the whole country), 全家 (quánjiā, the whole family). Japanese: on-reading ゼン (zen), kun まった.く (mattaku) and すべ.て (subete). 全部 (zenbu, all), 全体 (zentai, the whole), 安全 (anzen, safety), 全国 (zenkoku, nationwide), 全て (subete, all). Used daily as 全て (subete) and 全く (mattaku).

Memory aid: a flawless jade (玉) kept whole under a roof (入) — all, with nothing missing.