Every word for tea in the world traveled by one of two roads
Cha, tea, and chai sound unrelated until you trace them back to the same Chinese character and two different trade routes.
Order a cup of tea almost anywhere on Earth and the word you use will fall into one of three sound-families: something like te, something like cha, or something like chai. That's not a coincidence of unrelated languages converging by accident — it's a fossil record of how the plant itself moved.
All three trace back to a single Chinese character, 茶, whose pronunciation varied by region and era. Portuguese traders, working out of Macao in the 1590s, picked up the Cantonese cha and carried it into English as "char" before English settled mostly on the other form. Dutch traders arrived a few decades later working through Malay and Min Chinese ports, where the word was closer to te — and that's the pronunciation that spread through Dutch trade networks into English, French, and German as tea, thé, Tee.
The third branch went overland, not by ship. Cha traveled the Tea Horse Road into Central Asia and the Silk Road into Persia, where it picked up a Persian suffix, becoming chai, before moving into Hindi and eventually into English restaurant menus centuries later, alongside the tea it never quite merged with.
Say "chai tea" and you're technically saying "tea tea" in two languages descended from the same trade routes, six centuries and two oceans apart — the accidental rhyme of history rather than a coincidence of taste.