Fetching details from the dictionary...

to let leak; to let out (e.g. light)
to let out (a secret); to leak (information); to divulge; to disclose; to let slip
to give utterance to (e.g. one's dissatisfaction); to vent; to express; to reveal (e.g. one's true intentions); to let out (a sigh, etc.)
to wet one's pants
to omit; to leave out
to fail to do; to miss; to omit (by mistake); to forget to do
機密情報を漏らした。
He leaked classified information.
口が軽い同僚が重要な秘密をうっかり漏らしてしまった。
I accidentally revealed the secret.
会議の後で彼は同僚に上司への不満を漏らした。
He let slip his dissatisfaction.