flocculate
To collect (suspended particles, sediment, etc.) into loose, fluffy aggregations resembling tufts of wool.
When applied to clay soils it [lime] binds the small particles together, or flocculates them.
Where it comes from
Scientific internationalism; from Latin flocculus + -ate (etymology 1, 2 and 3), diminutive of floccus (“a lock, tuft”).
Adapted from the Wiktionary entry flocculate (CC BY-SA 4.0).