What weed is called the Irish daisy?

The common dandelion is the weed that is called the Irish daisy.

Specifically, the plant in question carries the scientific name Taraxacum officinale. It has a number of common names in honor of its beautiful, bright yellow top. One of the common names is "blowball" or "clock" in honor of the yellow flower head turning into a lovely round ball of silver-tufted fruit.