This expression, meaning “very fashionably and elaborately dressed”, is recorded from the 18th century. “The nine” or “the nines” were used to signify “superlative” in numerous other contexts. Theories include: 9, being the highest single-digit number, symbolized the best; a metanalysis of Old English to then eyne “to the eyes”; and a reference to the 9 muses
“Numbers are neither abstractions nor entities in themselves. Numbers are names applied to the functions and principles upon which the universe is created and maintained. Through the study of number - perhaps only through the study of number - these functions and principles can be understood.”
The Ennead (Ancient Greek: ἐννεάς, meaning a collection of nine things) was a group of nine deities in Egyptian mythology. The Ennead were worshipped at Heliopolis and consisted of the god Atum, his children Shu and Tefnut, their children Geb and Nut and their children Osiris, Isis, Set and Nephthys.