What a horrible name! I personally find Teal to be a very ugly color, and even if it wasn't it would be like naming your kid "Yellow" or "Red" or "Pink".
I've read that cyan is also a word for a greenish-blue color. So if you like the color enough to name your daughter after it, Cyan sounds MUCH cooler. This doesn't sound like much of a name anyway, and if it's a type of duck, it might lead to bullying. The name simply doesn't sound very nice. It sounds like 'steel' or 'steal'.