what if

Dates back at least to Old English hwæt ġif, of the same meaning.

what if (not comparable)

1. Used to introduce a suggestion or proposal for a future event.

   What if we arrange it for 9:00 instead of 10:00?

2. Used to introduce a speculation about a future event.

   What if we could learn to get along? What would happen then?

3. Used to introduce a speculation about a past event. Often the basis for counterfactual historical interpretations.

   What if Abraham Lincoln had not been assassinated? How might the Reconstruction of the Southern States have been handled?

• (introducing a suggestion): what about, how about

• what-if