To stop the flow of something, especially blood.
Stanched is a word used in serious situations, like when someone is hurt.
Examples:
The doctor stanched the bleeding with a bandage.
She stanched the wound with a clean cloth.
We need to stanched the water from the broken pipe.
He stanched the ketchup from spilling on his shirt.
The superhero stanched the flow of lava with his superpowers.
The plumber stanched the leak in the pipe.