Appendix:Korean sound symbolism

Modern Korean has a somewhat productive ideophonic ablaut process opposing "yin" and "yang" vowels. In modern Korean, these are primarily used for ideophones and sensory terms (e.g. color words). They were significantly more productive in Middle Korean (and presumably earlier forms), and have left a significant trace in the modern language even though most Koreans are no longer aware of them.

If Middle Korean lost some of the productivity of ablaut, it as a replacement innovated a productive system of consonant alternations based on a distinction between lenis, fortis, and aspirated consonants. Forms with fortis consonants are more intensifying than ones with lenis ones, and forms with aspirated consonants even more so.

The Korean ablaut system coincides with its vowel harmony system. Middle Korean vowel harmony, which governed the phonological shape of most native MK morphemes and the allomorphy of many verbal suffixes and most case- or topic-marking noun particles, took the following form (digraphs excluded):

Yin vowel	Yang vowel
ㅓ (e /⁠ə⁠/), ㅕ (ye /⁠jə⁠/)	ㅏ (a /⁠a⁠/), ㅑ (ya /⁠ja⁠/)
ㅜ (wu /⁠u⁠/), ㅠ (ywu /⁠ju⁠/)	ㅗ (wo /⁠o⁠/), ㅛ (ywo /⁠jo⁠/)
ㅡ (u /⁠ɨ⁠/)	ㆍ (o /⁠ʌ⁠/)
ㅣ (i /⁠i⁠/) (neutral)

Vowel harmony became weakened due to vowel shifts, particularly the conditioned merger of ㆍ (o /⁠ʌ⁠/) to ㅡ (u /⁠ɨ⁠/) word-internally and to ㅏ (a /⁠a⁠/) word-initially. Harmony is now vestigial, largely consisting of an opposition in the allomorphy of certain verbal suffixes. Note that the featural nature of the Hangul script makes the correspondences clearly visible:

Yin vowels	Yang vowels	Example
ㅓ (eo), ㅕ (yeo)	ㅏ (a), ㅑ (ya)	먹었다 (meog-eot-da, “one ate”) / 막았다 (mag-at-da, “one blocked”)
ㅜ (u), ㅠ (yu)	ㅗ (o), ㅛ (yo)	추었다 (chu-eot-da, “one danced”) / 보았다 (bo-at-da, “one saw”)

In both Middle and Modern Korean, verbs with "neutral" vowels take yin-vowel suffixes.

Semantic ablaut is more productive today than the harmonic system, involving a far wider range of vowels. All pairs ultimately derive from the Middle Korean oppositions. For instance, Middle Korean 의 (uy /⁠ɨj⁠/) opposed ᄋᆡ (oy /⁠ʌj⁠/); regular phonological change merged the former into ㅣ (i) and the latter into ㅐ (ae), explaining how an originally neutral vowel participates in the ablaut process.

Yin vowels	Yang vowels	Example
ㅓ (eo)	ㅏ (a)	꺼멓다 (kkeomeota, “to be sooty black”) / 까맣다 (kkamata, “to be pitch black”)
ㅔ (e)	ㅐ (ae)	데굴데굴 (deguldegul, “(of a big object) rolling”) // 대굴대굴 (daeguldaegul, “(of a small object) rolling”)
ㅕ (yeo)	ㅑ (ya)	여위다 (yeowida, “to be sickly gaunt”) // 야위다 (yawida, “to be gaunt”)
ㅝ (wo)	ㅘ (wa)	훤하다 (hwonhada, “to be somewhat bright”) // 환하다 (hwanhada, “to be bright”)
ㅞ (we)	ㅙ (wae)	휑하다 (hwenghada, “to be desolate”) // 횅하다 (hwaenghada, “to be deserted”)
ㅜ (u)	ㅗ (o)	둥그렇다 (dunggeureota, “to be biggish and round”) // 동그랗다 (donggeurata, “to be smallish and round”)
ㅟ (wi)	ㅚ (oe)	퀴퀴하다 (kwikwihada, “to be very musty (of smell)”) // 쾨쾨하다 (koekoehada, “to be somewhat musty (of smell)”)
ㅠ (yu)	ㅛ (yo)	쀼루퉁하다 (ppyurutunghada, “to be sullen”) // 뾰로통하다 (ppyorotonghada, “to be sulky”)
ㅡ (eu)	ㅏ (a)	뜨겁다 (tteugeopda, “to be hot”) // 따갑다 (ttagapda, “to sting (e.g. of an insect bite)”)
ㅢ (ui)	ㅐ (ae)	희멀겋다 (huimeolgeota, “to be murky whitish”) // 해말갛다 (haemalgata, “to be clear and white”)
ㅣ (i)	ㅑ (ya)	기우뚱 (giuttung, “tilted”) // 갸우뚱 (gyauttung, “somewhat tilted”)
ㅣ (i)	ㅏ (a)	심심하다 (simsimhada, “to be bored; to be tasteless”) // 삼삼하다 (samsamhada, “to be not salty but tasty”)
ㅣ (i)	ㅐ (ae)	시뻘겋다 (sippeolgeota, “to be blood red”) // 새빨갛다 (saeppalgata, “to be bright red”)

With a few exceptions, the system only works for purely native words, not Sino-Korean and especially modern English loans.

The yin-vowel form is dark/murky, and the yang-vowel form is bright/clear:

Yin-vowel	Yang-vowel
누렇다 (nureota, “to be dark yellow (like yellow clay)”)	노랗다 (norata, “to be bright yellow (like a newborn chick)”)
허옇다 (heoyeota, “to be murky white (like a hoary beard)”)	하얗다 (hayata, “to be bright white (like a cloud)”)

The yin-vowel form is heavy/loud/big, and the yang-vowel form is light/quiet/small:

Yin-vowel	Yang-vowel
쿵쿵 (kungkung, “boom-boom (like a fat person jumping)”)	콩콩 (kongkong, “thump-thump (like a little child jumping)”)
풍덩 (pungdeong, “falling into water (for e.g. a boulder)”)	퐁당 (pongdang, “falling into water (for e.g. a pebble)”)
둥둥 (dungdung, “floating in water”)	동동 (dongdong, “floating in water (of something small)”)
우뚝하다 (uttukhada, “to be protruding (for e.g. a mountain peak)”)	오똑하다 (ottokhada, “to be protruding (for e.g. a nose)”)

The yin-vowel form is dull/thick, and the yang-vowel form is sharp/thin:

Yin-vowel	Yang-vowel
뭉툭 (mungtuk, “blunt, stubby”)	몽톡 (mongtok, “blunt, stubby (of something thin)”)

The yin-vowel form is unpleasant, and the yang-vowel form is pleasant:

Yin-vowel	Yang-vowel
뚱뚱하다 (ttungttunghada, “to be fat, to be obese”)	통통하다 (tongtonghada, “to be plump, to be chubby”)
슬쩍 (seuljjeok, “subtly, furtively (of e.g. a thief)”)	살짝 (saljjak, “slightly, subtly”)
미끄럽다 (mikkeureopda, “to be slippery”)	매끄럽다 (maekkeureopda, “to be smooth to the touch”)
찍찍 (jjikjjik, sound of a rat)	짹짹 (jjaekjjaek, sound of a bird)

The yin-vowel form is intense, and the yang-vowel form is less so:

Yin-vowel	Yang-vowel
염치(廉恥) (yeomchi, “sense of honor”)	얌치 (yamchi, “(a certain) sense of honor”)
지랄 (jiral, “bullshit”)	재랄 (jaeral, “(a certain) bullshit”)

The yin-vowel form is old, and the yang-vowel form is young:

Yin-vowel	Yang-vowel
허허 (heoheo, an old man's laughter or warning)	하하 (haha, general laughter)
벙글벙글 (beonggeulbeonggeul, “old person's smile”)	방글방글 (banggeulbanggeul, “child's smile”)

The yin-vowel form is damp, and the yang-vowel form is dry:

Yin-vowel	Yang-vowel
퍼석퍼석 (peoseokpeoseok, “grainy and falling apart”)	파삭파삭 (pasakpasak, dry and crispy)
축축하다 (chukchukhada, “to be wet and damp”)	촉촉하다 (chokchokhada, “to be freshly wet”)

In many cases (perhaps the majority), one form is normal and the other form is marked or rare.

Ablaut was significantly more productive in Middle Korean. MK ablaut pairs not necessarily identifiable as such in Modern Korean include:

Yin-vowel	Yang-vowel
늙다 (nulkta, “to be old (of people)”) > 늙다 (neukda)	ᄂᆞᆰ다 (nolkta, “to be worn out”) > 낡다 (nakda)
븕다 (pulkta, “to be red”) > 붉다 (bukda)	ᄇᆞᆰ다 (polkta, “to be bright”) > 밝다 (bakda)
믉다 (mulkta, “to be watery”) > 묽다 (mukda)	ᄆᆞᆰ다 (molkta, “to be clear”) > 맑다 (makda)
거두다 (ketwuta, “to gather (of crops)”) > 거두다 (geoduda)	가도다 (katwota, “to jail (of criminals)”) > 가두다 (gaduda)
젹다 (cyekta, “to be few”) > 적다 (jeokda)	쟉다 (cyakta, “to be small”) > 작다 (jakda)

There are more controversial suggestions, including 너 (ne, “you”) vs. 나 (na, “I; me”), which would at least fit semantically.

In certain words, the MK form varied freely between the ablaut pairs, but either one was chosen in Modern Korean, or the two forms came to have different meanings.

Middle Korean	Modern Korean
머리~마리 (meli ~ mali, “head”)	머리 (meori, “head”)
	마리 (mari, “head”, counter for animals)
설~살 (sel ~ sal, “New Year; year of age”, since East Asians age up every New Year)	설 (seol, “New Year”)
	살 (sal, “year of age”)

Modern Korean distinguishes lenis, fortis, and aspirate consonants:

Caption text

Lenis	Fortis	Aspirate
ㄱ (g)	ㄲ (kk)	ㅋ (k)
ㄷ (d)	ㄸ (tt)	ㅌ (t)
ㅂ (b)	ㅃ (pp)	ㅍ (p)
ㅅ (s)	ㅆ (ss)	N/A
ㅈ (j)	ㅉ (jj)	ㅊ (ch)

The fortis forms are considered intensive, while the aspirate ones are para-intensive:

• 바삭바삭 (basakbasak, “crunchingly”)
• 빠삭빠삭 (ppasakppasak, “very crunchingly”)
• 파삭파삭 (pasakpasak, “extremely crunchingly”)

A tripartite division is not necessarily the most common; often, the aspirate form is missing, producing a bipartite division between a non-intensive lenis form and an intensive fortis form. For many forms, the lenis forms have become unusual and the default form is the fortis one.

This sort of emphatic fortition of the consonant is quite common in modern Korean slang, e.g. 진(眞) (jin) > 찐 (jjin).