Gastroesophageal reflux disease (GERD), gastro-oesophageal reflux disease (GORD), gastric reflux disease, acid reflux disease, or reflux (in babies and young children) is a chronic symptom of mucosal damage caused by stomach acid coming up from the stomach into the esophagus.
A replacement for the South Korean K200 series infantry fighting vehicles, formerly designated as K300 or XK21 KNIFV (Korea Next-generation Infantry Fighting Vehicle), is currently called the K21.
New!!: K21 (disambiguation) and K21 ·
The ASK 21 is a glass-reinforced plastic (GRP) two-seater mid-wing glider aircraft with a T-tail.
Soviet submarine K-21 was a K-class submarine of the Soviet Navy during World War II.
In geometry, a uniform k21 polytope is a polytope in k + 4 dimensions constructed from the ''E''''n'' Coxeter group, and having only regular polytope facets.
"Va, dal furor portata", K. 21 / K6 19c, is an early concert aria in C major for tenor and orchestra by Wolfgang Amadeus Mozart.