倍

Phono-semantic compound:

人 (사람 인) — semantic component, signifying “human” or general actions.

咅 (부, “to spit” / phonetic component) — provides the sound 배 (bèi).

Originally, 倍 denoted doubling or increasing something, both in number and in effort — hence its later use in mathematics, economics, and idiomatic expressions.

배 (倍) — a numerical multiplier meaning “times” or “fold”

두 배 (二倍) — double

세 배 (三倍) — triple

수배 (數倍) — several times

배가하다 (倍加하다) — to multiply, to increase greatly

배율 (倍率) — magnification, rate of increase

Example expressions:

加倍努力 (가배노력) — redouble one’s efforts

倍加 (배가) — increase, intensify

二倍速 (이배속) — double speed

倍率 (배율) — magnification (as in lenses or economics)

倍數 (배수) — multiple, multiplier

Linguistic note:

In modern Korean, 배 functions as a bound numeral unit denoting multiplicative comparison (“folds” or “times”).

However, a frequent misuse occurs when the particle 로 (by/as) is incorrectly added to verbs that already imply change or increase.

❌ Incorrect:

가격이 0.5배로 올랐다.

The price rose to half. (illogical — “rising to half” contradicts “rise”)

✅ Correct:

가격이 절반으로 내렸다.

The price dropped by half.

Another common misuse:

❌ 부담이 2배로 더해졌다.

(Logically invalid: “added by twice” = additive + multiplicative conflict)

✅ 부담이 2배 더해졌다.

(Correct, meaning “The burden doubled.”)

Thus:

“배로” implies as a ratio or result (often incorrect with additive verbs).

“배” without the particle is proper when expressing multiplication or proportional increase.

In Classical Chinese, 倍 also carried figurative meanings:

背信倍德 — to betray trust and virtue (“to double back on one’s word”).

加倍努力 — to redouble one’s effort (still used in modern Chinese and Korean).

The semantic evolution of 倍 reflects the human perception of doubling as intensification — not only in numbers but also in morality, emotion, and effort.