사이시옷 (saisiot)

What is 사이시옷 (saisiot)?
사이시옷 (saisiot) is a Korean word that refers to the consonant ㅅ(siot) that is inserted between two nouns to create a compound noun. When two words are combined to form a new compound word, "ㅅ(siot)" is added at the end of the previous word to indicate that the first syllable of the following word should be pronounced strongly.

When 사이시옷 is used?
사이시옷 is used to connect two nouns into a new compound noun that has a specific meaning. The meaning of the compound noun is usually related to the meanings of the two original nouns. For example, the word 고춧가루 (gochukkaru) is a compound noun made up of the words 고추 (gochu, "red pepper") and 가루 (garu, "powder"). The 사이시옷 ㅅ connects the two nouns and creates a new noun with the meaning "red pepper powder". The inserted "ㅅ(siot)" makes the sound of "가" in "가루" pronounced strong such as "까루." Thus, the pronunciation of "고춧가루" is "고추까루(gochukkaru)."

When two words are combined to make one word, ㅅ is added at the end of the preceding word that ends in a vowel to indicate that the following word sound should be pronounced strongly. Therefore, if the word that follows is a strong sound (ㄲ, ㄸ, ㅃ, ㅆ, ㅉ) or an aspirated sound(ㅊ, ㅋ, ㅌ, ㅍ), then 사이시옷(saisiot) is not used.

사이시옷(saisiot) is also used when the "ㄴ" sound is added between nouns. When "노래(Song)" and "말(Word)" are combined, it is pronounced as 노랜말(noraenmal), that is "ㄴ" is added between "노래" and "말". To use 사이시옷(saisiot) correctly, you must learn the standard pronunciation well. Even if the words end with the same "말(mal)", the reason why 사이시옷(saisiot) is used for ‘존댓말" meaning "Honorific words" and 사이시옷(saisiot) is not used for "인사말" meaning "Greetings" is because the standard pronunciations for each are 존댄말 and 인사말, respectively.

Key points about 사이시옷:

• 사이시옷 is not a sound that exists in any individual word. It only appears when two words are combined.
• 사이시옷 is only added to the end of the first word if the first word ends in a vowel.
• 사이시옷 is not used when the following word starts with an 거센소리 (aspirated sound: ㅊ, ㅋ, ㅌ, ㅍ) or 된소리 (fortis sound: ㄲ, ㄸ, ㅃ, ㅆ, ㅉ).

Examples when 사이시옷(saisiot) is used :
시냇가(sinaekka), 바닷가(badakka), 빗물(binmul), 아랫마을(alaenmaeul), 나뭇잎(namunnip), 깻잎(ggaennip).

Examples when 사이시옷(saisiot) is not used :

• 갈비찜 (galbijjim) - "grilled ribs" (갈비 (galbi) + 찜 (jjim)) - 사이시옷 is not used because 찜 starts with an fortis sound (ㅉ).
• 배탈 (baetal) - "stomach ache" (배 (bae) + 탈 (tal)) - 사이시옷 is not used because 탈 starts with an aspirated sound (ㅌ).
• 호떡 (hotteok) - "sweet pancake" (호 (ho) + 떡 (tteok)) - 사이시옷 is not used because 떡 starts with a fortis sound (ㄸ).