Which natural phenomenon is preceded by a noticeable fall in sea level?

what they fail to mention is that it is caused by earthquakes on converging tectonic plate and this causes a wave that increases in size

That's not entirely true. You can have Tsunami resulting from a massive landslide towards the ocean or a lake.

I've not heard of the tsunami

I answered Earthquake like most players but ( it is what it is ). ! ! !

Shaolintiger, A tsunami is caused by sudden and large-scale disturbances in bodies of water, most commonly triggered by underwater earthquakes where tectonic plates shift and displace vast amounts of water, but they can also result from volcanic eruptions, underwater landslides, or even meteorite impacts, all of which generate powerful waves that travel across oceans and can cause devastating effects when they reach coastal areas. (you failed to mention the "under the sea/ocean")

my most vivid nightmare is of following the sea water out until I see the massive wave , thankfully I woke up. Must be terrifying to be caught up in one.

Is tsunami not an underwater earthquake anyway?