ristagnare

Etymology 1
.

Verb

 * 1)  to become stagnant
 * 2)  to stagnate
 * 3)  to stanch, to block the flow of (a liquid)

Etymology 2
From.

Verb

 * 1)  to resolder or cover again with tin
 * 2)  to make (a barrel, boat, etc.) watertight