This is the 716th most frequent Thai word.
decc
The Thai word "เด็ก" (decc) means "child" or "kid" in English.
The word 'เด็ก' (decc) is used here as a noun meaning 'child' to refer to a young person.
เด็กคนนี้ชอบอ่านหนังสือมาก
This child likes to read books a lot.
In this sentence, 'เด็ก' (decc) functions as an adjective meaning 'young', describing age.
เขายังเด็กอยู่ ไม่ควรพูดจาแบบนี้
He/She is still young; they shouldn't talk like this.
Here, 'เด็ก' (decc) acts as a noun meaning 'child', used metaphorically to imply immature behavior.