1. growing old; aging
Usage: formal
2. showing the effects or weakness of old age
Usage: formal

Examples

• The senescent tree’s branches were brittle and bare.
• Scientists study senescent cells to understand the aging process.
• The senescent population requires more healthcare resources.
• Her senescent memory made it difficult to recall recent events.
• The company’s senescent technology needed urgent updating.
• Senescent leaves turn yellow and fall from the tree.