An aviation combines gin, lemon juice, maraschino liqueur and creme de violette. I got my recipe from David Lebovitz's Drinking French. We were introduced to the drink by our dear, departed friend The Playwright five years ago (see post).
I'd say the flavor is kind of like grape-flavor Pez. That's not necessarily a bad thing, though odd as there are no grape ingredients - could be a psychological trick with the purple color. And intensely purple it is! Interestingly, The Playwright's were darker:
My wife thinks his were also more bitter. I'm guessing he used the creme de violette in greater proportion. I know he used the same bottle because he gave it to us after that weekend - the maraschino liqueur, too. Generous guy.