The process how a colloidal substance (completely or partially dried) absorbs water is said to be imbibition.

Explanation: The substances that absorb water are known as hydrophilic substances. The colloidal substances are hydrophilic in nature. Cellulose, starch etc. present in the plant body are colloidal substances. They swell up by absorbing water and contract by losing water. The process of absorption of these kinds of colloidal substances is known as imbibition.

Example: The amount of water that a dry seed absorbs before germination is almost absorbed by imbibition method.

Importance of imbibitions:

i. The first step of water absorption by root hairs from soil is performed.
ii. Dry seeds become fit for germination by absorbing water through this method. The germination of seeds is dependent on imbibition method.