1. very steeply
2. very suddenly and dramatically

Examples

• The mountain path dropped precipitously into the valley below.
• Stock prices fell precipitously after the announcement.
• The cliff face rose precipitously from the ocean.
• Sales declined precipitously during the recession.
• The trail descended precipitously through the rocky terrain.
• His popularity dropped precipitously following the scandal.
• The road wound precipitously up the mountainside.