gastroscope

n. instrument for examining the interior of the stomach (inserted via the mouth)

In medicine (gastroenterology), esophagogastroduodenoscopy is a diagnostic endoscopic procedure that visualises the upper part of the gastrointestinal tract up to the duodenum. It is considered a minimally invasive procedure since it does not require an incision into one of the major body cavities and does not require any significant recovery after the procedure (unless sedation or anesthesia has been used). A sore throat is also common.
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Gastroscope /gas·tro·scope/ an endoscope for inspecting the interior of the stomach.gastroscop´ic gas·tro·scope n. [more]Gastroscope - Community and Resources

Noun
1. a type of endoscope for visually examining the stomach
(hypernym) endoscope

n. gastroscope, instrument for examining the interior of the stomach