Nobility

n. nobleness; aristocracy

Nobility is a government-privileged title which may be either hereditary (see hereditary titles) or for a lifetime. Titles of nobility exist today in many countries although it is usually associated with present or former monarchies. The term originally referred to those who were "known" or "notable" and was applied to the highest social class in pre-modern societies. In the feudal system (in Europe and elsewhere), the nobility were generally those who held a fief, often land and/or office, under vassalage, i.e. in exchange for allegiance and various, mainly military, services to the Monarch and at lower levels to another nobleman. It rapidly came to be seen as a hereditary caste, sometimes associated with a right to bear a hereditary title and, for example in pre-revolutionary France, enjoying fiscal and other privileges. Today, in most countries, "noble status" is a purely honorary dignity that confers no legal privileges; an important exception is the United Kingdom, where certain titles (titles of the peerage, until recently guaranteeing a seat in the Upper House of the UK Parliament, hence its name House of Lords), still confer some residual privileges.
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Noun
1. a privileged class holding hereditary titles
(synonym) aristocracy
(hypernym) elite, elite group
(hyponym) noblesse
(member-meronym) aristocrat, blue blood, patrician
2. the quality of being exalted in character or ideals or conduct
(synonym) magnanimousness, grandeur
(hypernym) honorableness, honourableness
(hyponym) high-mindedness, idealism, noble-mindedness
(attribute) noble
3. the state of being of noble birth
(synonym) noblesse
(hypernym) status, position
(hyponym) purple

(n.)
Those who are noble; the collictive body of nobles or titled persons in a stste; the aristocratic and patrician class; the peerage; as, the English nobility.
  

(n.)
The state of being of high rank or noble birth; patrician dignity; antiquity of family; distinction by rank, station, or title, whether inherited or conferred.
  

(n.)
The quality or state of being noble; superiority of mind or of character; commanding excellence; eminence.
  

This meant literally descent from a noble or aristocratic family. Despite this, there was an ongoing debate during the
Middle Ages on whether man was ennobled by his actions or by his heritage, something similar to our own ‘nature vs nurture’
debate. See also Of Four Quarterings.