immovable vs dead hand

immovable and dead hand both are nouns.

Word	Noun	Adjective	Verb	Adverb
immovable	Yes	Yes	No	No
dead hand	Yes	No	No	No

As nouns, dead hand is a hyponym of immovable; that is, dead hand is a word with a more specific, narrower meaning than immovable:

immovable: property consisting of houses and land
dead hand: real property held inalienably (as by an ecclesiastical corporation)

Other hyponyms of immovable include acres, demesne, estate, land, landed estate, land, mortmain.

immovable (noun)	dead hand (noun)
property consisting of houses and land	the oppressive influence of past events or decisions
	real property held inalienably (as by an ecclesiastical corporation)

immovable (adjective)	dead hand (adjective)
not able or intended to be moved