What is the meaning of Balu?

Third-person singular (hark), taking third-person singular (hura) as direct object, conditional indicative form of izan.

dead

Alternative form of bale (evil)

evil, malice

destruction

sand

flower

widow

dove

widower

dark green

parsley green

widow

thunder; the sound heard right after lightning strikes

accusative/genitive singular of ballu

Source: wiktionary.org