1.
tight-lipped, discreet, able to keep secrets
Describes someone who can be trusted with confidential information and won't reveal it to others.
彼女は口が堅いから、何でも相談できる。
She's discreet, so I can consult her about anything.
口の堅い人にしか話せない。
I can only tell this to someone who can keep a secret.
秘書は口が堅くなければならない。
A secretary must be tight-lipped.
STRUCTURE: 口 (mouth) + が + 堅い (hard/firm). Literally 'one's mouth is firm' - implying words don't escape easily.
ANTONYM: 口が軽い (loose-lipped, indiscreet)
PRENOMINAL FORM: 口の堅い + noun (a discreet [person])
RELATED EXPRESSIONS:
- 秘密を守る (to keep a secret)
- 信頼できる (trustworthy)
CULTURAL NOTE: Being 口が堅い is considered a valuable trait in Japanese business and personal relationships.
Related Words
Antonym:
口が軽い (loose-lipped)