1. a person or thing that provides support, nourishment, or maintenance to keep something going

Examples

• She was the main sustainer of her family during difficult times.
• The foundation serves as a sustainer of local arts programs.
• Rain is the primary sustainer of plant life in the desert.
• He became the financial sustainer of the charity organization.
• The river has been a sustainer of civilization for thousands of years.
• As the sole sustainer of the household, she worked two jobs.