訓

It is a phono-semantic compound, composed of:

言 (“speech, words”) as the semantic element;

川 (cheon, “river”) as the phonetic element.

The combination expresses the idea of words flowing like a river - instruction, explanation.

In modern and classical Korean, 훈 (訓) appears widely in the sense of teaching, instruction, or glossing:

교훈 (敎訓) – lesson, moral, instruction

훈계 (訓戒) – admonition, moral instruction

훈시 (訓示) – address, instruction (esp. by an authority)

훈독 (訓讀) – “gloss reading,” the native-language semantic reading of a Chinese character (cf. 음독, On-reading)

訓民正音 (훈민정음) – “The Correct Sounds for the Instruction of the People,” the original name of the Korean alphabet Hangul

Thus, 訓 has both a pedagogical meaning (“to teach, instruct”) and a linguistic meaning (“semantic gloss”), making it central in both education and the history of the Korean script.