This is the 16300th most frequent Korean word.
비밀이니까
"It’s a secret."
The word '비밀이니까' here indicates that the information shared is confidential and emphasizes the necessity of keeping it private, as shown by the imperative following phrase.
이건 비밀이니까 아무에게도 말하지 마세요.
This is a secret, so please don't tell anyone.
In this sentence, '비밀이니까' introduces the reason for adopting a quieter manner of speaking, connecting the concept of secrecy with subsequent actions.
비밀이니까 조용히 이야기할게요.
Since it's a secret, I will talk quietly.
Here, '비밀이니까' provides justification for the described behavior, explaining why certain information wasn't disclosed, emphasizing confidentiality.