Thanks, Mamya. It didn't matter that it had been answered before. I think I'm just surprised sometimes that posters don't look for earlier queries - and the PE crossword doesn't result in lots of threads. The niceness of the word was the real reason for my post!
Thanks, StevieGee. I'm hoping to drop the word, casually, into conversation sometime soon. Chambers describes it as American slang, for prison, jail - so your memories are validated!
Merriam Webster has an interesting entry for hoosegow and its Spanish /Latin origin. I tried to post it, but was refused. Hope the captcha works this time. I've almost given up with shopfronts and mountains. It only took half an our to post this :(