No. In fact, "though" is not a noun at all; it is a conjunction or adverb.
Yes, the noun astonishment is an abstract noun, a word for an emotional reaction.
Yes, the noun 'power' is an abstract noun, a word for an ability, a capacity, a strength, all things that are not physical in themselves, even though they are sometimes expressed physically.
Is undergone an abstract noun
Concrete noun
The abstract noun is criticism.
The noun 'hopefulness' is an abstract noun, a word for an emotion.
Abstract noun of hopeless
The abstract noun is obligation.
Friendship has not abstract noun because It is a abstract noun
The abstract noun form is tourism.
The abstract noun for the adjective vacant is vacantness. Another abstract noun form is vacancy.
The noun childhood is a singular, common, abstract, compound noun; a word for the time of being a child.