blabbermouth

blabber +‎ mouth

• (UK) IPA^(key): /ˈblæb.ə(ɹ)ˌmaʊθ/

• Audio (US)

  (file)

blabbermouth (plural blabbermouths)

1. (informal) A gossip.

   If it weren't for that blabbermouth Sally, the principal would never have known we did it.

2. (informal) A person who talks excessively.

   Synonym: chatterbox

3. (aviation) A kind of foam-dispensing nozzle used in firefighting at airports.
   • 1964, Civic Administration, volume 16, page 9:

     Two handlines are capable of 240 gpm and an undertruck "blabbermouth" nozzle can sweep the ground ahead at 240 gpm.

   • 1972, ICAO Bulletin, volume 27, page x:

     The monitor is fitted with a blabbermouth (variable nozzle) to enable jet-spray patterns to be obtained at will.

   • 1983, David F. Rider, Jane's Airport Equipment, page 210:

     A manually operated monitor is provided complete with blabbermouth to deliver foam solution at a rate of 2(KX) lures a minute at 10-5 bar, to a maximum jet range of 46 metres […]

• babblemouth