This is a strange looking word for an odd-looking color. It's really just "not quite purple", without being sufficiently different enough to become lavender or red. It just sits uncomfortably in the middle of that purple-to-red spectrum. Because it's not exactly a word you hear in every day conversation, you probably think it's pronounced "mow-ve", rhyming with "stove". And you'd be wrong.
Even though almost everyone gets it wrong - even the Doctor has been heard to do this on TV's Doctor Who, and he should really know better - the truth remains that the word is "maw-ve", where the "maw" sound rhymes with "saw". It may sound strange, but like we said, it's a strange color. At least you'll sound pretty impressive the next time you describe the awesome mauve shirt you just bought.