Mensa means “table.” It is also the name of a southern constellation mapped out by Nicolas Louis de Lacaille. Originally Lacaille meant for this area of the sky to be named “Table Mountain” after a place in Africa near Cape Town. People casually shortened the name to just Table and also shortened Nicolas Louis de Lacaille to just Lacaille.
Don’t expect to find this constellation easily. In terms of stars it is the dimmest of all 88 constellations. There is not a lot here in terms of deep sky stuff either, but part of the Large Magellanic Cloud (NGC 2070) edges across the cartographic boundary with Dorado. This has led to some to remark that Mensa resembles the real Table Mountain which is often capped by a cloud. That shows you just how desperate people can be to make some shred of meaning out of arbitrary maps and names etc.
There are no cute little stories about a table to go with the Mensa constellation, but there are several to go with the actual mountain. Table mountain is typically portrayed as kind of an asshat who summons storms to sink passing ships.
It’s apparent to me that Table Mountain must seek such mischief just for kicks because, unless I’m missing something here, I see no personal benefit for a mountain to sink a ship.