My understanding of salvation is that it implies that one is saved from something. I will admit that these may be a product of my primarily Christian culture.
Salvation means deliverance from the power and effects of sin. I think, "Salvation/Nirvana/Libretion/Moksha" all are same. The real meaning of this can be;
'to free your soul & body from all bondages, as bondages may be real cause of existances in bonded, arrested, concentrated or combined conditions instead of complete free & independant state--so real reason of pain/sin etc.
Nirvana has always seemed to me a concept which is open to a virtually endless range of interpretations; the closest I can come to understanding spiritual enlightenment from my sceptical point of view, is something like moral understanding which I suspect is a very poor fit.
a Nirvana should be salvation, & enlghtwnments is final blessed state marked by the absence of desire or suffering & to provide (someone) with moral or spiritual understanding or enlighten people from this ultimate knowledge. In one language this ultimate knowledge is called as
"Keval-gyan".
Libretion is a completely new term to me so I can't comment.
It is also alike salvation, means libretion of soul & body from all bondages.
Moksha is certainly part of the belief-system of the Yogic mysticism with which I am familiar.
Alike salvation, libretion, nirvana only.
I should make it clear, that I do not share any of the beliefs of Yogic mysticism I merely find the imagery pleasing and motivational. To me enlightenment is about acquiring knowledge and understanding and acting in accordance with that understanding. There is no mystical dimension to my version of enlightenment.
Yes, it is ok, but people just like these, directly or indirectly
I think one of the reasons that you encounter resistence amongst sceptics to your use of the term "absoluteness" is that it is probably not a very good translation of what you are trying to say. It has mystical connotations in our culture which are going to cause a lot of us to switch off before we give much attention to what you are trying to say. In general, I think it is a bad idea to try and reduce complex ideas to a single word such as absolutness even in one's own primary language but when you try to do it in another language you just don't know what cultural baggage your'e going to end up with.
I think, it is natural that people here don't like this word "absoluteness" i.e. free from imperfections due to 'current age/yuga' effects & entitlements. It is alike "GOD", "SALVATION", Enlightenment etc. which are ultimate.
The only mythology I am familar with in which salvation "can't be attained during current age" is that of the various Yugas in Hinduism (I think we are supposed to be living in Kali Yuga). Are there mythologies with a similar structure?
Yes, you are right.

. In Kaliyuga(present age), "salvation can't be attained" & "true basic knowledge of sastras(reputed books) can't be known/understood by "Brahmanas"(Learned people)". @nd one is by a curse of Godess Laxmi(Godess of money & luxuary)--which can mean, Due to the effect of money & luxuries, true basic knowledge can't be known by learned people. However, some exceptions are there to these mentionings. I feel & find, somewhat alike it.