Hangul syllable ggagg

Enter ㄲ, ㅏ, then final ㄲ.

On the standard Korean two-set keyboard (Dubeolsik), press Shift+R, K, Shift+R. The keyboard combines the initial consonant, vowel, and final consonant into one syllable block.

A Korean romanization keyboard takes Latin letters instead of Hangul keys; mappings vary, and some use gg for ㄲ. So ggagg is not a universal keystroke sequence.

What does 깎 mean in Korean?

It is the stem of a Korean verb for cutting and reducing.

Its object supplies the sense: peel an apple, trim hair, shape a material, lower a price, or damage someone's standing.

The verb appears in the 1447 Korean book Seokbo sangjeol, a retelling of the Buddha's life, in the Middle Korean form 가ᇧ다. This is an early written form of the verb, not the design date of the modern syllable block.

Why does 깎 look different after normalization?

The same syllable can be stored as one block or three jamo.

Unicode can store Hangul as one precomposed block or as conjoining jamo, the component letters used to build syllables: 깎 corresponds to ㄲ + ㅏ + ㄲ.

NFD stores the jamo separately; NFC normally composes them into one block. If you see the components separately, they still represent the same syllable.