1. most difficult to hold onto or stand on because of being smooth, wet, or greasy
Usage: superlative form of slippery
2. most evasive, untrustworthy, or difficult to pin down
Usage: figurative use; superlative form of slippery

Examples

• The bathroom floor was the slipperiest surface in the house after the leak.
• Ice makes roads the slipperiest during winter storms.
• That politician is the slipperiest character I’ve ever encountered.
• The wet rocks by the waterfall were the slipperiest part of the trail.
• He’s the slipperiest negotiator in the business.
• The soap made my hands the slipperiest they’d ever been.
• This is the slipperiest slope on the entire mountain.