If something or someone is your “cup of tea,” you like it or them. It’s more commonly used in the negative form these days, as in, “he’s not my cup of tea.”
The phrase has been in use since the late 1800s when the British started using the phrase “my cup of tea” to describe what or who they liked. Tea has been around for a long time, and so has the British slang term for it, which is “char.” The Mandarin word “ch’a” was used before it was called “tea.” Other tea-related phrases still in use are, for example, “Not for all the tea in China,” and “I could murder a cup of tea.”
In the early 20th century, a ‘cup of tea’ was such a synonym for acceptability that it became a metaphor for invigoration. The first time the term appeared in print was in Nancy Mitford’s Christmas Pudding, in 1932, “I’m not at all sure I wouldn’t rather marry Aunt Loudie. She’s even more my cup of tea in many ways.”
The negative usage began in WWII. An early example of it is found in Hal Boyle’s Leaves From a War Correspondent’s Notebook column, which described English life and manners for an American audience. [In England] You don’t say someone gives you a pain in the neck. You just remark “He’s not my cup of tea.”
Another example is seen in a literary work by James Agate, who wrote the figure of speech in one of his literary works. It was first published in 1939 and reads: “For assuredly immersion in medieval legend is not my cup of tea.”
The change from positive to dismissive doesn’t reflect the national taste for the drink itself. Tea remains “our cup of tea” in the UK. According to the United Kingdom Tea Council, 60 million Brits down 160 million cups of tea each day.
My English genes seems to have been lost somewhere along the way, because I find tea neither invigorating nor interesting. I should probably say, instead, that sweeping leaves out of my carport is “not my cup of coffee.”