At the end of Infinity War, Thanos succeeded in wiping out half the universe in an instant. The latest tie-in book has revealed this event as “The Decimation”. It sounds like a perfect name, evoking memories of a similar tragedy that struck the X-Men in the comics.
Marvel has been careful in avoiding the consequences of the Snap, so as to not give out any spoilers for Avengers 4. Except for one post-credits scene of Ant-Man & The Wasp, none of the films has been set in this period. Even Marvel TV shoes dodged the Snap, whose fifth season was heavily influenced by Thanos’ attack. With Brandon T. Snider’s The Cosmic Quest Vol 2: Aftermath, we get some throwaway references to the chaos caused by the snap. But it has now given an official in-universe name for the event which was earlier stated as “The Snappening” by fans.
To the remaining people of Earth, the moment is called “The Decimation”. The Avengers have made sure to keep the reason behind the snap a secret, perhaps figuring that the knowledge of Thanos and Infinity Stones would hardly help the world to heal. The planet is grieving and all they know is that their loved ones were turned to dust.
The Decimation has been taken from the comics where it refers to the horrific aftermath of “House of M” event. That story saw Scarlet Witch depower all except a tenth of world’s Mutants. This left many Mutants in hazardous situations, perhaps many even committing suicide, being unable to cope with the loss of their powers.
The two Decimations have a few striking similarities as both were initiated by a single being and transformed the world in one instant and led to grief and widespread suffering.