noun

• The beginning of something.
• The source of a river, information, goods, etc.
• (mathematics) The point at which the axes of a coordinate system intersect.
• (anatomy) The proximal end of attachment of a muscle to a bone that will not be moved by the action of that muscle.
• (cartography) An arbitrary point on Earth's surface, chosen as the zero for a system of coordinates.
• (in the plural) Ancestry.