tight-lipped.

Unwilling to reveal information or discuss feelings.

Use it for

Words that belong together

• remain tight-lipped
• a tight-lipped official

On the page

The captain remained tight-lipped about what the divers had found.

Usage notes

Primary category: literary / elevated general. Forms: Comparative more tight-lipped; superlative most tight-lipped when comparison is meaningful. Legacy lexical fields mirror sense 1 only. Use numbered sense fields for all meanings. Established modern English lexical item. No separate regional spelling or grammatical inflection entry. Writing functions: description, character. Commonness: moderately common.