お茶 - Wiktionary
2019-3-13 · Usage notes []. お茶 generally refers to a cup of hot green tea. In general, black tea is referred to as 紅茶 (kōcha), though it can be implicitly included within the term お茶, which literally just means "tea.". The honorific お (o-) in お茶 is normally written in hiragana, though you will see it from time to time in more formal or official writing as 御 (as in 御茶).
