Trench Mouth Meaning

(idiomatic, medicine) Acute necrotizing ulcerative gingivitis, a severe bacterial infection of the gums, typically characterized by inflammation, bleeding, deep ulceration, necrotized tissue, pain, fever, enlarged lymph nodes, fatigue, and halitosis.

Example: 1918, "Discover New War Disease: British and French Soldiers Suffering from ‘Trench Mouth’," New York Times, 17 Jun., p. 7 (retrieved 7 Jan. 2009),
  "Trench mouth" is one of the war diseases which is engaging the attention of British army doctors.
2002, Itzhak Brook MD, "Anaerobic Bacteria in Upper Respiratory Tract and other Head and Neck Infections," Annals of Otology, Rhinology & Laryngology, vol. 111, no. 5, p. 433:
  Vincent's angina (or trench mouth) is a distinct form of ulcerative gingivitis.