If they have gill looking things on the underneath side are the mushrooms or toadstools?

Question

lanre · Answer

The two are similar and are fungi, but the difference is that the TOADSTOOL may have gills underneath it.

lanre · Answer

So, toadstools.

anonymous · Answer

As far as I know, the two terms can often be used interchangeably. The word "toadstool" often is used to describe fungi with that classic stalk plus umbrella-like cap shape, especially if they're poisonous or fairy tale-related. But the "mushrooms" that we find in the supermarket have a similar shape, and they also have those gill-like structures on the underside of the cap.

anonymous · Answer

scientifically toadstool has no meaning but could be considered synonymous with mushroom. colloquially toadstool is something that is poisonous of that you just don't like. all toadstools are mushrooms but not all mushrooms are toadstools.
the technical name for fungi with gill-like reproductive structures (mushrooms/toadstools) is basidiomycete