Actually, that's a picture of a carrot flower, but dill is a relative with extremely similar flowers and seeds. Except that, in my opinion, dill seeds make better tea than carrot seeds.
The family Umbelliferae, defined as "plants having flowers in umbels: parsley; carrot; anise; caraway; celery; dill," contains both food plants, herbals, and poisonous weeds (poison and water hemlocks, for example).
Under the umbrella *wink* of the Umbellirerae are many plants:
There's a genus Seseli which is supposedly something called "moon carrots." I know nothing about them other than that they have an intreguing name; the genus Daucus provides our carrots.
Other genuses are also useful, Pastinaca includes parsnips. Apium is celery. Carum gives us caraway; and predictably Cuminum is cumin. The genus Petroselinum covers the parsleys. Pimpinella is, strangely, anise; and Anethum is dill -- which I am having this morning.
Dill is a useful herb for settling an upset stomach. As an herbal infusion, or tea (I take mine sweetened) it is very pleasant. Not at all like dill pickles -- which is what you were thinking, right? Dill pickles are good too, but, no, I don't take vinegar in my tea. Vinegar is an aide to digestion and combined with dill does make an excellent addition to the diet, but that's a topic for a different post.