According to the Setswana-English dictionary (pula press 1977):
lekgoa, n., A European; an English person.
Almost all of the African languages consists of word-classes, eg class for (singular/plural): people (mo/ba); things (le/ma) etc.
Le: the class for things
kgoa: n., pl. dikgoa, A bush louse; a species of tick, found chiefly on the hinder parts of animals.
Although many of these cultures outgrown their language-meanings,this word is used for derogation purposes.
see also: legoa pointing as white man or boer.
The lekgoa was the creators of apartheid: The white man(insulting) was the creators of segregation (direct translation=separateness)