ennoble

v. make noble, raise the level of excellence, refine; give someone a title of nobility

Nobilitation means the act of making one a noble - a member of the noble social class. Depending on time and region, various laws governed who and how could be nobilitaded. Typically nobilitation was conferred on individuals who had assisted the sovereign. In some countries (e.g. France of Ancien Regime, this degenerated into the buying of nobility, where rich commoners (e.g. merchants) could buy a noble title.
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(v. t.)
To raise to the rank of nobility; as, to ennoble a commoner.
  

(v. t.)
To make noble; to elevate in degree, qualities, or excellence; to dignify.
  

Verb
1. confer dignity or honor upon; "He was dignified with a title"
(synonym) dignify
(hypernym) honor, honour, reward
2. give a title to someone; make someone a member of the nobility
(synonym) gentle, entitle
(hypernym) promote, upgrade, advance, kick upstairs, raise, elevate
(hyponym) baronetize, baronetise
(derivation) ennoblement