My brother moved to New York in the late 80s when it was still pretty awesome. He lived in Manhattan in an area called Alphabet City because the streets there are lettered (map). At the time, there were drug dealers on his block, there was a salvage yard catty-corner from his place and the eating and drinking establishments were occupied by people who weren’t tattooed ironically. Like I said, it was pretty awesome.
The southern border of the area is Houston Street which, still being very much a Midwesterner the first time I went, I pronounced like the city in Texas: Hewston. Dead giveaway. It’s House-ton and provides the line between NoHo (North of Houston) and SoHo (South of Houston). That part’s easy to figure out, but when I came across London’s area called Soho (note lack of capitalization on the H) I couldn’t make heads or tails of why it was called that. Whenever I remembered, I asked people who’d lived in London or were English and they hadn’t known, so the question lingered.
Of course, this was long before the magic that is the Internet existed. Now, most knowledge ever possessed by English-speaking people is readily available so I can report that Soho, like tallyho, was a hunting cry and that both have “ho” in common with the Spanish hola.