bitesizekorean:

The National Institute of Korean Language decreed that the Seoul “dialect" is how modern Korean should be spoken. Hence the Seoul accent is considered the standardised Korean dialect (표준어). Yet like any country, and with any language, you will come across many different dialects.

Gyeongsang: The people of the Gyeongsang Province, which includes cities like 부산, 대구, 마산, 포항, 경주 etc, speak 경상도 사투리, which is considered one of the harsher dialects.

There are quite a few notable differences between standardised Korean and the Gyeongsang dialect, but I will only list a few of significance. For example, 경상도 speakers are often unable to pronounce ㅆ when it appears at the beginning of a word, such as 쌀 (rice) and so it will often be pronounced 살.

Speakers of this dialect also miss the vowel sound for “ㅡ” which has a “eu” sound, and will instead replace it with “ㅓ” and pronounce it with an “oe” sound. This means words such as 음악 “music” will be pronounced like 엄악.

Gyeongsang dialect also has difficulty with compact vowels, such as ㅘ or ㅢ, which means that it is common for the first vowel of a compact vowel to be dropped. So words like 사과 “apple” is pronounced like 사가, and 의사 “doctor” is pronounced like 이사.

Chungcheong: Chungcheong is quite close to Seoul, so there are very few notable differences between Chungcheong and standardised Korean. The biggest difference between the two, is that people of Chungcheong have the tendency to speak really slowly. Alongside this, it is also very common for speakers to replace ㅗ with ㅜ, and ㅛ with ㅠ, especially with verb conjugations. For example, instead of saying 하세요, it might be very common to hear 하세유, or even the shortened form 하슈.

Gangwon: Gangwon is a large province, bisected by the high Taebaek mountain range, so historically, very few people lived in the area. The Western part of Gangwon has no physical barrier between itself and Seoul, so for the most part, no significant dialect was developed. However, on the Eastern coast, Gangwon did develop a few unique dialect differences. The most notable being a speaker’s tendency to use tones to distinguish the meaning of homo-phonic words. This dialect also has quite a few words that are very unusual.

Jeolla: Jeolla has its very own and very distinctive dialect. Jeolla’s dialect is also slower than Seoul’s, but much faster than Chungcheong speakers, and it also contains frequent ups and downs in sound. The most distinctive part of Jeolla is the vowel conjugations, since it is a very common characteristic to end sentences with 잉. Similarly, the ending ~요 is replaced with ~이라 or ~어라, and the vowel conjugation ~데 is changed to ~디 in this dialect.

It is also very common to add extra ㅅ and ㅂ in within certain words, like how the word 더워 (hot) is pronounced 덥어. It is also common for ㅏ and ㅓ to be pronounced as ㅐand ㅔ. For example, the word 마음 (mind) is pronounced as 매음.

Jeju: Jeju is the most geographically isolated population, so much so, Jeju speakers have such an unbelievably unique dialect that it is almost completely a separate language! Jeju dialect is still grammatically Korean, but with a very unrecognisable vocabulary. This is due to the island’s isolation and neighbouring influence. The dialect still maintains extremely old Korean words, whilst seeking inspiration from Japan, China, and even Mongolia. 

Vowel conjugation is also notably different. The basic honorific ~요 is replaced with ~ㅂ서, and instead of ~ㅂ니까, the honorific question is ~꽈.

Seoul/Gyeonggi: Even though Seoul dialect is considered “standard Korean”, Seoul/Gyeonggi still embellish in their own individualised dialect quirks. However, the differences are so slight, the dialects are practically indistinguishable. Although, a common habit with Seoul/Gyeonggi speakers is they continuously mispronounce specific words in a certain pattern. This dialect habit entails replacing ㅗ with ㅜ, such that 삼촌 (uncle) will be pronounced like 삼춘.