Gari Ledyard proposes that ㅁ (m) was derived from the lower part of ㅂ (b). The traditional account* holds that its form is the outline of the mouth, 口形 (it is nearly identical with the Chinese pictographic character for mouth, 口), and Ledyard feels this consideration may have determined the final forms of ㅂ and ㅁ.
* Hunmin Jeongeum Haerye "Explanations and Examples of the Proper Sounds for the Instruction of the People" (1446), defining and explaining the script now known as 한글 (Hangeul, “Great script, Korean script”) in South Korea and 조선글 (joseon'geul, “Korean script”) in North Korea.
- 미음 (mieum), a jamo (letter) of the alphabet of the Korean writing system, hangeul; the bilabial nasal (IPA(key): /m/)
In the North Korean order, ㅁ (m) is the fifth jamo. In the South Korean order, it is the seventh.
- ㅂ (b) (in traditional account)
- the act of; the process of; -tion; -ion; -ing
- 기르다 (gireuda, “to grow, raise”) + ㅁ (m): 기름 (gireum, “cultivation”)
- 자다 (jada, “to sleep”) + ㅁ (m): 잠 (jam, “a slumber, nap”)
If the verb stem ends with a consonant, 음 (eum) is appended instead:
- 갚다 (gapda, “to repay”) + 음 (eum): 갚음 (gapeum, “repaying”)
- 남다 (namda, “to profit”) + 음 (eum): 남음 (nameum, “profiting”)
- 기 (gi)