saturate
to soak or fill completely
Root
- sat / satis: enough, full, satisfied, or filled
Other words with the sat / satis root
- insatiable: impossible to satisfy; always wanting more
- satiate: to fill beyond need
- satisfy: to meet a need or make enough
Saturate is fullness taken all the way through: every space is loaded or soaked.
The storm saturated the field until each step sank into mud.