急

Phono-semantic compound:

心 (마음 심) — semantic, expressing feelings, anxiety, or agitation.

及 (미칠 급) — phonetic, giving the sound and the notion of reaching or catching up.

Originally, 急 depicted “the heart (心) that hastens to reach (及) something,” expressing inner tension, haste, or anxiety.

In clerical script (隸書 lìshū), the upper part 及 sometimes took the variant form similar to 刍, leading to the modern shape.

긴급 (緊急) — emergency, urgency

급박 (急迫) — pressing, imminent

급선무 (急先務) — matter of utmost priority

급행 (急行) — express train, rapid movement

급변 (急變) — sudden change

급성 (急性) — acute (as in medicine)

급식 (給食) — meal provision (from the idea of quick serving)

급증 (急增) — sudden increase

In classical Chinese, 急 signifies not only haste or speed but also emotional urgency or distress:

《論語》: 「君子欲訥於言而敏於行，不患人之不己知，患不知人也。」— "The gentleman acts quickly but not rashly", where 敏 and 急 are contrasted.

《孟子》: 「無為而治者，其順民之情而應之也。急者緩之，緩者急之。」— “He who governs effortlessly adjusts to the people’s temperament: when they are too hasty, he makes them calm; when they are too slow, he quickens them.”

In Buddhist texts, 急 can express urgency in spiritual practice — the need to awaken quickly before life ends, e.g., 急於修行 “to hasten in cultivating the Way.”

In East Asian vocabulary, 急 contrasts with 緩 (완, “느릴 완”) — the duality of urgency vs. calmness, forming common expressions like 急緩 (급완, “urgency and relaxation”), emphasizing balance and timing.

In modern usage, Korea and Japan tend to use 急行 (급행) for “express,” while modern Chinese favors 快车 (쾌차) or 快速 (쾌속) — replacing 急 with 快 for a more natural collocation in Mandarin.