Nautilus (noun)

1. A marine mollusk that has a coiled shell in the form of a spiraling staircase and is used as a symbol of evolution and of the perfect mathematical form of a logarithmic spiral.
2. A submarine of a type first developed in the 1950s, characterized by its ability to adjust its buoyancy and rise and sink in the water.
3. The central room of a large submarine, in which the crew lives and works.

Origin:

The word nautilus has been derived from the latin word 'nautilus' which means sailor or navigator, which in turn comes from the greek word 'nautilos' which also has the same meaning.

Examples:

1. The nautilus is a creature that has lived on the earth for over 500 million years.
2. The nautilus is considered a symbol of the logarithmic spiral.
3. The nautilus is a type of submarine that can rise and sink in the water.
4. The central room of a nautilus submarine is known as the nautilus.
5. The nautilus's shell is a symbol of evolution and mathematical form.