Pronunciation: (lang'ku-stur; for 4–8 also lang'kas-tur),[key] —n. 1. the English royal family that reigned 1399–1461, descended from John of Gaunt (Duke of Lancaster), and that included Henry IV, Henry V, and Henry VI. Cf. York (def. 1).
2. a member of this family.
3. a city in Lancashire, in NW England. 125,500.
4. a city in SE Pennsylvania. 54,725.
5. a town in S California. 48,027.
6. a city in central Ohio. 34,953.
7. a town in N Texas. 14,807.
8. a town in W New York. 13,056.