Dane a Viking invader of the British Isles in the 9th–11th centuries; the term in this sense, broadly covering all Norse invaders of the period and not just those coming from Denmark, is recorded from Old English.
Danegeld a land tax levied in Anglo-Saxon England during the reign of King Ethelred to raise funds for protection against Danish invaders; the term is also given to taxes collected for national defence by the Norman kings until 1162. The word is now often used allusively with reference to the likelihood that buying off an enemy will ensure their return for further payment, a view popularized in a poem by Kipling, ‘What Dane-geld means’ (1911).
Danelaw the part of northern and eastern England occupied or administered by Danes from the late 9th century until after the Norman Conquest.
danewort a dwarf elder with a strong, unpleasant smell and berries yielding a blue die that was formerly used to colour leather. The name derives from the folklore that the plant sprang up where Danish blood was spilt in battle.

Dane native of Denmark XIII; breed of dog XVIII. — ON. Danir pl. (late L. Danī); superseding OE. Dene, which is repr. in Denmark (OE. Denemearc).
So danegeld tax imposed c. 1000. XI. — ON. *Danagjald (ODa. Danegjeld), f. g. pl. of Danir Danes + gjald payment, tribute (cf. YIELD). Danelaw the Danish laws anciently in force over the part of England occupied by the Danes, (hence) the region itself. Late OE. Dena lagu ‘Danes' law’, ME. Denelawe, was modernized by Lambarde (1576) as Dane lawe, and taken up by historians of XIX in the forms Danelage, -lagh, -law.

Dane / dān/ • n. a native or national of Denmark, or a person of Danish descent.