Eph 2:1 And you hath he quickened, who were dead in trespasses and sins;
The word indeed is nekros, indicating dead, or spiritually dead in context but again referring to separation. The word is used 132 times in various contexts.
For example, in the second chapter of James:
James 2:17 Even so faith, if it hath not works, is dead, being alone.
James 2:20 But wilt thou know, O vain man, that faith without works is dead?
James 2:26 For as the body without the spirit is dead, so faith without works is dead also.
In each of the above four cases the word for death is nekros or as you say, corpse. "Faith, if has not works is "corpse."
Well no. If faith is separated from works, James says it is alone, "being alone," and therefore without works it is "a corpse"?? No again. If faith is separated from works there is no corpse, that is not the point. It simply means that the faith is useless. The works must proceed from the faith to be of any use. The faith is still there. It is not as a corpse, lifeless, non-existent. It is inoperable, unable to produce works or the right kind of works.
DHK,
First, you are incorrect about James 2:20. The word is not nekros it is ἀργή (argē). It means useless.
Second, your exegesis is flawed. James 2:17 literally means that faith is dead by its own standards. Nekros, always a physical term, is used for effect. One could interpret it in the vernacular "faith, if it has no works, is like a corpse. It is that dead."
Verse 26 is a play on words. Just the like the body without the spirit is dead, so also faith without works is dead. James bring σῶμα (soma) into the sentence. Soma is a physical body. Nekros is a dead body. The connect is clearly made. Even when a corpse is not the object it adds emphasis to the object, in this case faith.