(physics) equilibrium length (length of a spring, etc. at rest)

naturalists (as a group) or naturalist (individual), promoting a closer connection with nature (lifestyle, food, etc.)

spontaneous combustion

to spontaneously combust

natural right

a land, a large place / a country in general, a region / a country as in a nation, a state / the office of emperor, the crown; affairs of state / a province of ancient Japan

a surname

country, nation, nation-state

home country (usually refers to Japan)

Japan