bund

can be a noun meaning either:

• a league or confederacy; especially the confederation of German states.
• a secondary enclosure, typically consisting of a wall or berm, which surrounds a tank or fluid-handling mechanism, intended to contain any spills or leaks.

or a verb meaning 'to provide berms or other secondary enclosures to guard against accidental fluid spills within' (Wiktionary)

Variations: bund, bunded, bunding, bunds.