虛

Phono-semantic compound consisting of:

虍 (호피 무늬 호) — phonetic element, giving the sound hū / heo, representing the tiger’s pattern or fierceness.

丘 (언덕 구) — semantic element, meaning “hill” or “mound.”

In Shuowen Jiezi (說文解字), Xu Shen defines:

「虛，丘也。从虍丘聲。」

“虛 means a hill; composed of 虍 and the sound 丘.”

Thus, the earliest sense of the character was “a large mound” or “an empty elevation.”

Later, the meaning shifted metaphorically to denote emptiness, vacuity, or falsehood — a conceptual movement from “hollow hill” to “void.”

虛 (빌) — empty, vain, false

虛空 (허공) — the void; empty space; sky

虛心 (허심) — humble heart; open-mindedness

虛弱 (허약) — weakness; frailty

虛偽 (허위) — falsehood; hypocrisy

虛名 (허명) — empty name; unearned reputation

虛實 (허실) — emptiness and fullness; false and real

虛飢 (허기) — hunger from emptiness; craving

虛病 (허병) — illness from deficiency (medical sense)

In Daoist philosophy, 虛 represents a central virtue: the quality of emptiness or receptivity.

Laozi (道德經) says:

「致虛極，守靜篤。」

“Attain utmost emptiness, and hold firm to stillness.” (Daodejing, ch. 16)

In this context, 虛 is not mere absence but a fertile void — the source from which all things arise.

Similarly, Zhuangzi (莊子·人間世) teaches:

「虛室生白，吉祥止止。」

“In an empty chamber arises light; where emptiness abides, good fortune dwells.”

In Buddhist texts, 虛空 (허공) denotes the limitless void — the spatial and spiritual expanse wherein all phenomena appear and vanish, symbolizing the nature of śūnyatā (emptiness).

In medical classics such as the Huangdi Neijing (黃帝內經), 虛 describes internal deficiency — “vital emptiness” of qi or blood causing weakness, faintness, or chronic illness (虛證).

Korean traditional medicine retains this sense in words like 허약체질 (constitutionally weak) and 허기 (empty hunger).

Thus, 虛 spans the full semantic field from physical hollowness to moral humility and metaphysical emptiness — a character bridging body, mind, and cosmos.