Fennel (Foeniculum vulgare), is a plant species. It is a hardy, perennial, umbelliferous herb, with yellow flowers and feathery leaves. It is generally considered indigenous to the shores of the Mediterranean, but has become widely naturalised elsewhere (particularly, it seems, areas colonized by the Romans) and may now be found growing wild in many parts of the world, especially on dry soils near the sea-coast and on river-banks.
It is a highly aromatic and flavorful herb with culinary and medicinal uses, and is one of the primary ingredients of absinthe. Florence fennelor finocchio is a selection with a swollen, bulb-like stem base that is used as a vegetable.
The word fennel developed from the Middle English fenel or fenyl. This came from the Old English fenol or finol, which in turn came from the Latin feniculum or foeniculum, the diminutive of fenum or faenum, meaning "hay". The Latin word for the plant was ferula, which is now used as the genus name of a related plant. As Old English finule it is one of the nine plants invoked in the pagan Anglo-Saxon Nine Herbs Charm, recorded in the 10th century.
Fennel is a perennial herb. It is erect, glaucous green, and grows to heights of up to 2.5 m, with hollow stems. Theleaves grow up to 40 cm long; they are finely dissected, with the ultimate segments filiform (threadlike), about 0.5 mm wide. (Its leaves are similar to those of dill, but thinner.) The flowers are produced in terminal compoundumbels 5–15 cm wide, each umbel section having 20–50 tiny yellow flowers on short pedicels. The fruit is a dryseed from 4–10 mm long, half as wide or less, and grooved.