you wont find "Bible" in the Bible either, i guess the Bible doesnt exist?
the main passage that teaches the rapture is first thessalonians 4:17
"Then we which are alive and remain shall be caught up together with them in the clouds, to meet the Lord in the air: and so shall we ever be with the Lord."
this was originally written in greek and the phrase "harpoza" is translated "shall be caught up" in English, but in the latin translation it is "rapturo"
and it literally means to be snatched up