Where does “Karabük” come from?

Karabük (English) comes from Turkish Karabük, from Ottoman Turkish قره بوك, from Ottoman Turkish قره, from Ottoman Turkish آغاج, from Proto-Turkic ïgač — tree.

Ancestry of “Karabük”, step by step

Step	Language	Word	Meaning
1	Turkish	Karabük	—
2	Ottoman Turkish	قره بوك	—
3	Ottoman Turkish	قره	black; alternative form of قاره
4	Ottoman Turkish	آغاج	tree
5	Proto-Turkic	ïgač	tree

Every word from Proto-Turkic ïgač →Every word from Ottoman Turkish آغاج →Every word from Ottoman Turkish قره →