If you at all care about what a name really means, don't look here. Normally I'd say that the best place to get a good meaning is the Oxford Dictionary of First Names, but almost all other name books I've seen are more accurate than this one, which seems to make up meanings to make names seem more attractive when the original meaning is not the most becoming- for example, does this book mention that Addison means "son of Adam," or that it's the name of a disease? No, they say it means "awesome." Names are composed of linguistic elements the same way words are, so just like you can't decide that the word "flower" means "rotten stump" one day and have everyone agree with you, you can't arbitrarily assign meanings to names.
Beyond the blaring inaccuracies in this volume, the author needs to look up the meaning of the word "unique" in the dictionary.
There is a glut of baby name books on the market, and this is at the bottom of the heap for quality. I'd recommend The Baby Name Wizard for style ideas and the Oxford Dictionary of First Names if you care about meaning or usage. Also, Rosenkrantz and Satran's latest, The Baby Name Bible, is pretty good and informative, and supposedly contains over 50,000 names.