Pendos is a slur used to describe Greeks in a derogatory way. Used by Russians as a derogatory term for Greeks. There has been a sizable Greek community in southern Russia for many generations. Many of them originally hailed from the Pontus region of Turkey. Hence Pontus=Pendos.
The word Pendos is a racial slur that has been used historically to degrade and dehumanize greeks. The word is still used by some people for this purpose, and it is seen as offensive and hurtful to greeks. If you are unsure about whether or not it is appropriate to use the word Pendos, it is best to err on the side of caution and avoid using it in any situation.