1. most likely to form clumps or stick together in lumps
Usage: superlative form of clumpy
2. most awkward or ungraceful in movement
Usage: informal; superlative form of clumpy

Examples

• This is the clumpiest mascara I’ve ever used.
• The clumpiest soil in the garden needs more compost.
• Her clumpiest dance moves made everyone laugh.
• The clumpiest oatmeal was at the bottom of the pot.
• He felt like the clumpiest person on the dance floor.
• The clumpiest paint wouldn’t spread evenly on the wall.