I came across a fascinating website earlier, Tsiosophy, devoted to the history of tea and other tea-related things. The modern word in English, tea, has gone through many variants in its history. Seemingly, the word for tea in most 16th-century Chinese dialects was cha, and the OED does have early citations with this spelling, but the dialect of the locals who Dutch traders would have dealt with when importing tea to Europe pronounced the Chinese character for tea as te, and this was the form adopted into English (so says OED).
The words cha, chah, char, chai and tsia are all in the OED as either early forms of ‘tea’, or slang words (cha or char is still very common in Britain now). Those are the headwords – there are many more variant spellings listed that are not headwords eg tcha, chau, chaw, tay, tey, thea and others.
Tsiology is also listed as a nonce-word (ie used once for a specific book or reason). In this instance Tsiology was the title of an 1827 scholarly dissertation .
There is far more about tea and the different words for tea – and it’s far more erudite than this post – on this Tsiosophy page (a word meaning ‘the wisdom of tea’, according to the author).