The act of maintaining oneself at a minimum level.
Embodiment or personification or hypostasis of an underlying principle or quality.
Real being; existence.
Inherency.
Something (food, water, money, etc.) that is required to stay alive.
Maintenance; the act or effort of keeping something in good and working condition.
Do you know how to upkeep a boat?
To maintain (something) or keep it in good repair.