There are actually only three possible options regarding the question or claim of God’s existence.
Once we define God as Ultimate Reality, the claim that “Ultimate Reality exists” results in only three possible choices.
We can accept the claim that Ultimate Reality exists, reject the claim that Ultimate Reality exists, or suspend judgment about the claim that Ultimate Reality exists.
The atheist rejects the claim that Ultimate Reality exists. The deist and theist accept the claim that Ultimate Reality exists, while the agnostic suspends judgment about it.
It has become popular for atheists to claim that they withhold belief in God due to a lack of evidence. But this position is not atheism; it is agnosticism. Their zeal against anyone who believes in God shows that they actually reject the claim that God exists. But they cannot defend that claim, so they redefine their position to avoid the glaring irrationality.