1. in a rusty manner; with rust or corrosion
2. in a way that shows lack of practice or skill due to disuse

Examples

• The old gate creaked rustily as it swung open.
• The hinges moved rustily after years of neglect.
• He played the piano rustily after not practicing for months.
• She rustily attempted the dance steps she once knew well.
• The machinery operated rustily due to poor maintenance.
• The chain rattled rustily in the wind.