Before (preposition)

1. During the period of time preceding (a particular event or time).
2. In front of.

Origin:

Old english beforan, from be- 'by' + foran 'in front, before'.

Examples:

1. We arrived at the theater before the show started.
2. She always finishes her work before the deadline.
3. Please arrive at least 15 minutes before your appointment.
4. The sun rose before our eyes.
5. He stood before the judge and pleaded guilty.