Fennel seed water is simply water infused with fennel seeds, either through immersing them in hot water or steeping it overnight in cool water. Fennel water has a light golden colour, smells fresh and clean, and the taste is not bad at all! In the beginning, I did find the taste weird but I got used to it real quick.
Fun fact: Fennel seeds or fennel water actually has a mild licorice flavor, so it leaves a sweet taste in your mouth, and is actually potent breath freshener.