Kikuyu or Gikuyu (Gĩkũyũ ) is a language of the Bantu family spoken primarily by the Kikuyu people (Agĩkũyũ) of Kenya. Numbering about 7 million (22% of Kenya's population), they are the largest ethnic group in Kenya. Kikuyu is spoken in the area between Nyeri and Nairobi. Kikuyu is one of the five languages of the Thagichu subgroup of the Bantu languages, which stretches from Kenya to Tanzania. The Kikuyu people usually identify their lands by the surrounding mountain ranges in Central Kenya which they call Kĩrĩnyaga.
Kikuyu has four main mutually intelligible dialects. The Central Province districts are divided along the traditional boundaries of these dialects, which are Kîrînyaga, Mûrang'a, Nyeri and Kiambu. The Kikuyu from Kîrînyaga are composed of two main sub-dialects – the Ndia and Gichugu who speak the dialects Kĩndia and Gĩgĩcũgũ. The Gicugus and the Ndias do not have the "ch" or "sh" sound, and will use the "s" sound instead, hence the pronunciation of "Gĩcũgũ" as opposed to "Gĩchũgũ". To hear Ndia being spoken, one needs to be in Kerugoya, the largest town in Kîrînyaga. Other home towns for the Ndia, where purer forms of the dialect are spoken, are located in the tea-growing areas of Kagumo, and the cool Kangaita hills. Lower down the slopes is Kutus, which is a bustling dusty town with so many influences from the other dialects that it is difficult to distinguish between them.The dialect is also prevalent in the rice growing area of Mwea.
The unmistakable sing-song Gichugu dialect (which sounds like Meru or Embu, a sister language to Kikuyu) can be heard in the coffee-growing areas of Kianyaga, Gĩthũre, Kathũngũri, Marigiti. The Gichugu switch easily to other Kikuyu dialects in conversation with the rest of the Kikuyu.