Both the adjective and the noun are 'palace', for example:
Noun: A palace fit for a princess.
Adjective: The palace politics will keep you on your toes.
Palace is a noun (a structure). However, it can be used as a noun adjunct (rather than an adjective) in compound nouns such as palace gate and palace guard.
palatial.
The word 'weakest' is the superlative form of the adjective 'weak':positive: weakcomparative: weakersuperlative: weakest
The word 'famously' is the adverb form of the adjective 'famous'.The noun form of the adjective 'famous' is famousness.The word 'famous' is the adjective form of the noun fame.
The noun form of the adjective 'angry' is angriness.The word 'angry' is the adjective form of the noun anger.
Palace is a noun (a structure). However, it can be used as a noun adjunct (rather than an adjective) in compound nouns such as palace gate and palace guard.
The incredible-looking mansion looked like a palatial palace.
The noun form for the adjective authentic is authenticity.
The noun form of the adjective 'dangerous' is dangerousness.The word 'dangerous' is the adjective form of the noun danger.The noun form of the adjective 'childish' is childishness.The word 'childish' is the adjective form of the noun child.The noun form of the adjective 'beautiful' is beautifulness.The word 'beautiful' is the adjective form of the noun beauty.
palatial.
The noun form of the adjective 'wide' is wideness.A related noun form is width.
The noun form of the adjective 'comfortable' is comfortableness.The word 'comfortable' is the adjective form of the noun comfort.
The abstract noun form of the adjective unique is uniqueness.
The noun form of the adjective 'modest' is modestness.A related noun form is modesty.
The noun form for the adjective hilarious is hilariousness. A related noun form is hilarity.
The abstract noun form for the adjective convenient is convenience.
The noun form of the adjective 'considerate' is considerateness or consideration.