1. a person who goes on dates or is dating someone
Usage: informal
2. a device or tool used to mark or stamp dates

Examples

• She’s a serial dater who goes out with someone new every week.
• He’s not much of a dater and prefers to meet people through friends.
• The office dater broke, so we couldn’t stamp the documents.
• Use the automatic dater to mark today’s date on each form.
• My sister is an active dater and uses several dating apps.
• The postal worker used a dater to cancel the stamps.