The opening sequence of any event.
The opening kick of each half of a game of football.
The opening sequence of notes in a song, usually played by the song's main instrument, to indicate the beginning of the song.
The beginning of something.
The proximal end of attachment of a muscle to a bone that will not be moved by the action of that muscle.
An arbitrary point on Earth's surface, chosen as the zero for a system of coordinates.
The source of a river, information, goods, etc.
Ancestry.
The point at which the axes of a coordinate system intersect.