This refers to a type of black ink commonly used in calligraphy and painting, particularly in East Asian cultures. It is often made from soot and other materials and is typically sold in solid form (ink sticks) that must be ground on an ink stone before use.

This meaning refers to the dark fluid produced by squids and octopuses, often used as a culinary ingredient for flavoring and coloring dishes, especially in some Asian cuisines.

This usage refers to a tool used by carpenters to create straight lines or to transfer measurements accurately. The string is coated with ink, allowing for a marked line when snapped against a surface.