| mega- | <physics, prefix> Metric prefix indicating 1,000,000 times a given quantity. For example, a megawatt is 1,000,000 watts. (29 Oct 1998) |
|---|---|
| mega-oesophagus | <radiology> Achalasia, Chagas disease, idiopathic pseudo-obstruction, amyloidosis, Ehlers-Danlos syndrome, presbyesophagus (uncommon), oesophageal dysmotility (usually mild to moderate dilatation) (12 Dec 1998) |