催

催 is a phono-semantic compound composed of:

人 (사람 인) — the semantic component, representing human action or effort.

崔 (높을 최) — the phonetic component, contributing the sound cuī / choe and implying height or prominence.

Originally, the word denoted pressing upon or urging a person, metaphorically extending to urging circumstances or emotions.

Over time, it acquired the causative nuance “to make something happen sooner.”

催促 (최촉) — to urge, to press, to hasten

催眠 (최면) — hypnosis; “to induce sleep”

催化 (최화) — catalysis; to accelerate a reaction

催淚 (최루) — tear-inducing, e.g. 催淚彈 (tear gas)

催生 (최생) — to induce birth or bring forth (figuratively: to foster creation)

The core sense “to urge” (to prompt someone toward completion) expanded metaphorically to include natural processes:

歲月催人老 — “Time urges people to grow old.”

風雨催花落 — “Wind and rain hasten the falling of blossoms.”

Thus, 催 bridges external pressure and inevitable natural progression — a common poetic motif in classical Chinese.

In Korean, 재촉하다 is a direct calque from the Sino-Korean 최촉(催促), later naturalized as a native verb.

Hence, the hanja 催 preserves a clear etymological trace within modern Korean vocabulary.

Modern Chinese and Japanese extended 催 metaphorically into scientific vocabulary:

催化劑 (catalyst) — “an agent that urges (促) chemical change.”

催眠術 (hypnosis) — “the technique of inducing (催) sleep.”

These reflect the consistent causative nuance — “to bring about through stimulation.”