I'm sure I should have known, but I've just discovered that the word spa is short for 'sanitas per aqua' in Latin or health through water in English. I learned this from a new book I read over the weekend. It was about the UNESCO World Heritage Site where Zenith is based - Bath: City on Show. I was invited to its launch last week. Appropriately, the building for the reception has engraved on its pediment the words 'Water is best' ... in Greek.