The study of filterable pathogens is an important part of virology.

He feels dizzy when he stands up suddenly due to orthostatic hypotension.

Special relativity is one of the fundamental theories of physics.

General relativity is a theory of physics proposed by Einstein.

He ended up spoiling the ship for a ha'p'orth of tar because he didn't pay back a small debt.

The Empire of Japan, written as 大日本帝國 in Kyūjitai, was a nation that existed from 1868 to 1945.

The Imperial Japanese Army was a Japanese military force that existed from the Meiji era to the Showa era.

The Imperial Japanese Navy was once the navy of Japan.

The Winter Triangle is a shape that connects the brightest stars in the night sky.

The Greater East Asia Co-Prosperity Sphere is a concept proposed by Japan during World War II.