Mbugu had only three colour terms in the sense of basic colour term as Berlin & Kay (1969) use that concept: black-white-red. The word 'unripe' may be used for yellowish colours and the word for 'grass' for 'green'. I have not done a colour naming test for Mbugu; I don't know what they would do when forced to name colours. Value 5 is choosen to mean "neither".