1. a person or thing that ages something, or a substance used to accelerate aging
Usage: technical or specialized use
2. a person of a specified age (used in combination, as in 'teenager' or 'ager')
Usage: informal; usually in compounds

Examples

• The winemaker used a chemical ager to speed up the maturation process.
• Teenagers are sometimes called 'agers' in developmental psychology.
• The ager in the concrete mixture helped the material set faster.
• Middle-agers often face unique career challenges.