Adjective: blabbermouthed 'bla-bu(r),mawthd or 'bla-bu(r),mawdhd
- Prone to communicate confidential information
"The blabbermouthed employee caused tension in the office";
- leaky, talebearing, tattling
- Unwisely talking too much
"The blabbermouthed employee leaked confidential information to the press";
- bigmouthed, blabby, talkative
See also: communicative, communicatory, indiscreet