Yes, Bill, 'iota' is the Greek cognate for 'yod', both letters being the equivalent of 'i' or 'j' and written as a small single stroke. From iota, comes the English word 'jot'. In the NT, Jesus, speaking of the Jewish law, says that not a jot or a tittle of it shall pass away (King James translation). A tittle, according to MW Collegiate, is a small mark, such as a diacritical mark, from the Latin 'titulus'. So St. Jerome has it that not an iota or a titulus shall pass away.