The story
From post- + tribulation + -ism.
Etymology from Wiktionary, CC BY-SA 4.0.
Today it means: The belief or doctrine that Christians will not be Raptured, or transported bodily to Heaven, before the Tribulation, but rather received or gathered in the air by Christ to establish the Kingdom of God on earth after the Tribulation. Full definition →
From post- + tribulation + -ism.
Etymology from Wiktionary, CC BY-SA 4.0.