la la la

said loudly to prevent the speaker from hearing something he/she doesn't want to hear

Japanese Meaning

聞きたくない会話や音を隠すために、大声で無意味な歌詞や音（“la la la”）を発する表現 / 不快な内容を遮断するために使われる、意図的な無意味な発声表現

When he tried to tell me the secret, I went 'la la la' loudly to block his words.

彼が私に秘密を話そうとしたとき、私は彼の言葉をかき消すために大声で「ららら」と歌った。

Sense（1）

said loudly to prevent the speaker from hearing something he/she doesn't want to hear

I'm turning up the volume when you speak 'Cause if my heart can't stop it I find a way to block it, I go la la, la la la la la