An inquiry into the development of nouns in the Korean language since the fifteenth century, in the light of morphological construction and variation, will reveal the following facts:
1. Korean nouns can be classified largely into simple words and compound words in morphological construction and the latter can be further divided into compound nouns and transformed nouns.
2. Simple nouns are those which cannot be analyzed into more than two morphemes, such as "믈(水)", "힘(力)", "사ㄹㆍㅁ(人)", and 구룸(雲)".
3. Compound nouns, consisting of a noun and an other word, are divided as follows;
(1) Noun+noun : 날ㄷㆍㄹ(日月), 안팟(內外), 돌ㄷㆍ리(石橋), 암캐(牝狗), 신코(履端), 妻家집
(2) Adverb+noun : ㄱㆍㅅ쉰(正五十), 납작코(低鼻)
(3) Attributive adjective+noun: 긜짐승(獸)
(4) Stem+noun: 흘긔눈( 안), 검버섯(黑瘢), 곱상(美相), 밉상(醜相)
4. Transformed nouns are those which were transformed from other words. Examples follow:
(1) Root>noun: 번게(電), 울에(雷)
(2) Noun>noun: 므스>므슴(何), 그력>그려기(雁), 받>바닥(底), 갖>가죽(皮), 막대>막대기(杖)
(3) Stem>noun: 열다>여름(實), 살다>사리(治), 깊다>기픠(深)
(4) Adverb>noun: 개구리(蛙), 부헝이(휴)
5. Some compound nouns change in form, as we can see in the following examples: 바다길>바닷길(海路), ㄱㆍ라ㆍ비>ㄱㆍ랑비(細雨), 오리비누이>오누이(男妹), 어제저녁>엊저녁(昨夕)
6. Nouns are transformed into other parts of speech as follows:
(1) Noun>verb
A. Some nouns are directly tranformed into verbs. Examples: ㄱㆍㅁㆍㄹ>ㄱㆍㅁㆍㄹ다(旱), 되(升)>되다(量), 신>신다(履)
B. Some nouns are transformed into verbs when a suffix is added. Exaples: 자(尺)>자히다(度), 쪽(片)>쪼개다(破)
(2) Noun>adjective
A. Some nouns are directly transformed into adjectives. Examples: ㅎㆍㅣ(日)>ㅎㆍㅣ다(白), 믈(水)>묽다(淡)
B. Some nouns are transformed into adjectives when a suffix is added. Examples: ㄴㆍㄹ(刃)>ㄴㆍㄹ캅다(銳), 새>새롭다(新), 곳(香)>곳답다(美)
(3) Noun>adverb: There are two cases of the transformation of a noun into an adverb.
A. Direct transformation: 나날(日日), 때때(時時), 잠간(暫間)
B. Transformation made when a suffix is added: 새로(新), 스스로(自), 몸소(自)
(4) Noun>attributive adjective: As in the cases of (1), (2), and (3) above, there are two cases of the transformation of a noun into an attributive adjective.
A. Direct transformation: 여러(諸), 새(新), 갓갓(物物)
B. Transformation made when a suffix is added: 므스>무슨(何), 물>뭇(衆)
(5) Noun>particle: Some nouns are transformed into particles as follows: ㄱㆍ장>-ㄱㆍ장(極), 다히(方向)>-대(處)
7. Some nouns are always used as a suffix to other words. Examples: 해(物) in "내해" and "네해", 치(毛) in "새치(白毛)"
Some nouns are always used as a prefix to other words. "산男" in 사나이(男) is a good example.
8. Some nouns are used only when they follow an attributive-adjective-fomed word or an attributive adjective, and they are classified as follows:
(1) Time: 적, 즈음
(2) Place: ㄷㆍ, 데, 억
(3) Person: 이, 분
(4) Things: 이, 것, 바, 줄, ㄷㆍ, ㅅㆍ
(5) Number: ㅇㆍㄹ, 올, 에, 재(둘재, 셋재), 번, 만, 섬, 만, 말, 되
9. Some nouns irregularly inflect as follows:
(1) Irregular inflection in morphology: "놀(鹿)이, 놀-ㅇㆍㄴ, 놀-ㅇㆍㄹ", "노ㄹㆍ-도, 노ㄹㆍ-와"
(2) Irregular inflection in phoneme: "ㄱㆍㅅ(邊)-이>ㄱㆍㅿㅣ>ㄱㆍ이"
(3) Irregular inflection in vocal sound: "ㅁㆍㄹ(馬)-이" and "ㅁㆍㄹ(宗)-이" are different; in the former case, it inflects as "ㅁㆍ리" and in the case of "棟", it inflects "ㅁㆍㄹ이" and "ㅁㆍㄹ리".