The only Bible writer to use the word “antichrist” is the apostle John. Note these words in the first letter bearing his name:

“Young children, it is the last hour, and just as you have heard that the antichrist is coming, even now many antichrists have appeared, from which fact we know that it is the last hour. They went out from us, but they were not of our sort . . . Who is the liar but the one who denies that Jesus is the Christ? This is the antichrist, the one who denies the Father and the Son.”—1 John 2:18, 19, 22.

Therefore, the Anti-Christ would come up with a Universal teaching that opposes Jesus as the Christ, the son of the living God. (Mathhew 16:16)