What Pali or Sanskrit words in Buddhism are usually used to mean 'Realization'?
Without using a dictionary I think the English word "realize" has two meanings:
- Literally, "to make real" or "to actualize" -- e.g. "he realized his objective" -- where the word "real" to me means, literally or etymologically, "thing-like" or "tangible"
- Figuratively, "to understand" -- e.g. "I realized what you were saying"
When it's used in the context of Buddhist "enlightenment" I think that it's the second meaning, and that it's a one-word summary of what's described in more detail in SN 56.11:
‘This is the noble truth of suffering.’ Such was the vision, knowledge, wisdom, realization, and light that arose in me regarding teachings not learned before from another.
So it's Pali words like ñāṇa ("knowledge, understanding"), paññā ("wisdom; knowledge; insight"), vijjā ("higher knowledge; science").
Is Nirvana a Realization?
A better question might be, "do you understand it?"' -- or, referencing SN 56.11 again, has it "been understood?" (i.e. using the "perfect tense" to denote a completed action).
English-language grammar distinguishes nouns and verbs, i.e. "things" and "actions" -- and to say that Nirvana is a noun ("it is a realization") implies that it's some kind of thing, which is confusing -- and it's an example of "reification" (which is one of the themes of the post in question).
Is Realization a nama-dhamma (mental phenomena) or can it be an asankhata-dhatu (unconditioned phenomena)?
Did you ever read and enjoy Zen and the Art of Motorcycle Maintenance? The question reminds me of the bit about four fifths of the way through -- where he warns against Aristotle's classifying everything, and being a "professional academician", the theory that "dialectic comes before everything else", and the protagonist's complaint that what he considers primary is arbitrarily classified as a subcategory of something else.
But I think another answer on this site said it's conditioned -- that the act or process of enlightenment depends on conditions (e.g. "the factors of enlightenment").