The literal meaning of the late Boris Berezovsky's surname is 'birch tree' (берёза, pronounced 'beryoza', is birch tree in Russian). Coincidentally, the name of the Icelandic singer Björk also means 'birch tree'.
Most words for the tree in Germanic and Slavonic languages are similar. It is believed that the words all stem from a common Proto-Indo-European root *bherəg’-, meaning something bright or shining. The English word bright originates from the same PIE root.
Interestingly, the Latin fraxinus, is also a cognate of *bherəg’-. It's hard to see the link, I know, but the PIE sound /bh/, an aspirated vocal stop, changed into other sounds down the centuries, depending on the language. This explains why blaze and flagrant (= burning) come from the same PIE root, and why bleat and the Latin verb flēre, to cry or weep, are related. However, the Latin fraxinus is not a birch tree; it's an ash. Scholars have speculated that the birch, a tree that grows in cool and temperate climates, may not have been familiar to the original inhabitants of warmer, southern European countries, so they applied the same stem meaning 'shining' to a familiar tree that also appeared to be bright and shining.