What is the meaning of Blak?

Indigenous (Aboriginal and Torres Strait Islander).

An Indigenous Australian.

black

a thrown object

a throw

buttermilk

singular imperative of blaken

first-person singular present of blaken

flapping, waving (e.g. in the wind)

light blow

volleyball

the tail of a halibut

black (of a black color)

black (having black skin)

black-haired

dark, blackish

alternative form of blake (“pale, yellowish”)

black

Source: wiktionary.org