How to quote a definition from a paper which cites another paper for the definition I have to write the definition for a term in my Paper. I find the best definition for the term in a particular paper, say paper1. I would like to quote the definition as it is in my paper. I believe this is not wrong and is not plagiarism, as I am quoting the definition with proper references. Please correct me if I am wrong.

Now, the author of paper1 in her paper cites a paper for the definition, say paper2. But in  paper2 I cannot find the exact wordings which I would like to quote, or else I could have quoted from paper2.

Now how do I quote this term definition. Do I need to cite both the papers or shall I put the quote with citation of paper2 as it is from paper1, and then cite paper1.

Please advise me what is the proper convention that is followed.
In general, citing the original source is the way to go. As long as you cite correctly there is no need to worry about plagiarism.

Consequently, you should cite paper2. Since you cannot find the exact wording of the quote in paper1, I would suggest you paraphrase the quote and cite the original source with your own words. 

This would be much better than citing the already referenced quote in paper1.