I bid on some and can't seam to visualize 14 cm bulb and how big or small it would be.

14 cm is the circumference or distance around the bulb. Dividing 14 by 2.54 (the number of centimeters per inch gives us 5.5 inches around. Then, dividing 5.5 inches by 3.1416 will give the diameter, something that's meaningfull. In this case that would be 1.75 inches across.

14 cm is considered optimum size for lily growers and gardeners alike for many reasons.

Edit added: The US Fifty Cent Coin is very near 14 cm or 1.75 inches.

It would be the size of a good sized tulip bulb; tulips are commonly sold at 12 cm circumference (just to help visualize).