The noun Mzungu is used in East Africa, particularly in former British colonies like Kenya and Uganda, to describe white persons or more specifically Europeans. Mzungu is Swahili and its plural form is wazungu.
I've gotten two explanations towards the actual meaning of the word. One from Kenya and one from Uganda:
- The people who walk around. Apparently the first Europeans coming to what is now Kenya travelled around in order to "discover" it. These busy persons were nicknamed mzungus.
- Helper. In Uganda the word mzungu means helper and refers to white persons. By saying just mzungu, it is assumed you are talking about white people, but my mzungu means helper as in the original meaning of the word.
StrawberryFrog informs me that Umlungu means 'white' in xhosa.
Sources:
Joseph from Nairobi and E2's own Gritchka.