liberty vs leave of absence

liberty and leave of absence both are nouns.

Word	Noun	Adjective	Verb	Adverb
liberty	Yes	No	No	No
leave of absence	Yes	No	No	No

As nouns, leave of absence is a hypernym of liberty; that is, leave of absence is a word with a broader meaning than liberty:

liberty: leave granted to a sailor or naval officer
leave of absence: the period of time during which you are absent from work or duty

Other hypernyms of liberty include leave.

liberty (noun)	leave of absence (noun)
an act of undue intimacy	the period of time during which you are absent from work or duty
immunity from arbitrary exercise of authority: political independence
freedom of choice
personal freedom from servitude or confinement or oppression
leave granted to a sailor or naval officer