With a few minor exceptions, there are really only two ways to say “tea” in the world. One is like the English term — té in Spanish and tee in Afrikaans are two examples. The other is some variation of cha. Te entered the English language in the 1600s. But then in the 1970s, cha, the second root word for tea, made its way into the English language as well. This time it was through the Hindi word cāy. But English already had a way to say tea. So, chai in English has instead come to mean a specific kind of tea: Spiced Indian tea, which is known in India as masala chai. Masala chai is basically Hindi for “spiced tea”. Chai tea, on the other hand, means “tea tea” and it is a redundant expression.

Source: Medium