口(くち)を滑(すべ)らせる

くちをすべらせる
expression
to let something slip; to say something by mistake
communication
1. to let something slip; to blurt out; to say something unintentionally
To accidentally reveal information or say something one didn't mean to, often a secret or something inappropriate.
つい口(くち)を滑(すべ)らせてしまった。
I accidentally let it slip.
秘密(ひみつ)を口(くち)を滑(すべ)らせて言(い)ってしまった。
I blurted out the secret by mistake.
サプライズパーティーの計画(けいかく)を口(くち)を滑(すべ)らせて本人(ほんにん)に話(はな)してしまい、みんなに怒(おこ)られた。
I accidentally let the surprise party plan slip to the person themselves, and everyone got mad at me.

Literally "to let one's mouth slip." A vivid idiom where the mouth is imagined as slipping on something, causing words to come out unintentionally.

Usage

Often preceded by つい (unintentionally, inadvertently), emphasizing that the speaker didn't mean to say it. The expression always implies the speaker regrets what was said. Used in both casual and formal contexts.

Common collocations

  • つい口(くち)を滑(すべ)らせる — to inadvertently let it slip
  • 口(くち)を滑(すべ)らせてしまう — to end up blurting it out (with regret)
  • 秘密(ひみつ)を口(くち)を滑(すべ)らせる — to let a secret slip

Similar words

  • 口走(くちばし)る — to blurt out; to say rashly without thinking
  • 漏(も)らす — to leak; to let information escape
  • 失言(しつげん) — a slip of the tongue; a verbal gaffe (noun)

Related Words

Compare: 漏(も)らす (to leak)
Compare: 失言(しつげん) (a slip of the tongue)
Compare: 口(くち)が滑(すべ)る (to let something slip)
general
Added 2026.3.26 20:48 · Revised 2026.9.2 13:01
19500/19678_kuchiwosuberaseru