Language contact in Tanzania is promoted by language planning policies which strengthen Swahili and English as official languages and Media of Instruction (Mol) in primary schools. Consequently, in rural areas, Swahili dominates ethnic community languages (ECLs) and affects their lexicons. In most cases, additive borrowing is experienced because many new concepts penetrate into ECLs through Swahili. This paper shows how borrowed Swahili nouns penetrate into semantic fields linked to the modern world, clothing and grooming, religion and belief, and agriculture and vegetation in Hadzabe and Maasai. Since Swahili penetrated into Maasai districts and Hadzabeland about a century ago, prevalent contact situations result in additive borrowing where Swahili nouns penetrate into the lexicons of Hadzane (Hadzabe) and Maa (Maasai). In addition, borrowed Swahili nouns are assigned to the gender and number systems in Hadzabe and Maasai. These are the main morphological changes which are handled in this paper.