'Libertarian' definitions:

Definition of 'libertarian'

From: WordNet
noun
An advocate of libertarianism
noun
Someone who believes the doctrine of free will [ant: necessitarian]

Definition of 'Libertarian'

From: GCIDE
  • Libertarian \Lib`er*ta"ri*an\ (-t[=a]"r[i^]*an), a. [See Liberty.] Pertaining to liberty, or to the doctrine of free will, as opposed to the doctrine of necessity. [1913 Webster]

Definition of 'Libertarian'

From: GCIDE
  • Libertarian \Lib`er*ta"ri*an\, n. One who holds to the doctrine of free will. [1913 Webster]