let something slip

idiomatic

(idiomatic) To accidentally reveal a secret.

Japanese Meaning

うっかり秘密を漏らす / 意図せず秘密を明かす

I accidentally let something slip about the surprise party, and now everyone knows.

私はサプライズパーティーのことをうっかり漏らしてしまい、今ではみんな知っています。

Sense（1）

(idiomatic) To accidentally reveal a secret.

We were talking about Natalie when I let slip that she was pregnant.

lets something slip

（ present singular third-person ）

letting something slip

（ participle present ）

let something slip

（ participle past ）

let something slip

（ past ）