약

Etymology 1
, from the Middle Korean reading.

Noun

 * 1) drug; medicine

Etymology 2
, from the Middle Korean reading.

Adverb

 * 1) approximately; about

Etymology 3
.

Noun

 * 1) an ancient notched vertical bamboo flute of Chinese origin with three fingerholes used today only in Confucian ritual music and dance in South Korea

Etymology 4
Korean reading of various Chinese characters.