I prefer "Anvil".

"A subtype of Cumulonimbus" just doesn't do the trick for me.
Spotted en route to the "Milkery": it is, I think, possibly the first fairly reasonably Anvil shaped one I remember seeing.

Nothing to do with the cloud ...
There's a rude(ish) song, explaining why dogs sniff one another's bits, it starts:-
By Royal Proclamation dogs came from near & far,
some came by Shanks's Pony and others came by car
......
I saw the Visitors'/comments book they have in the "Milkery" and thought of that song....
See extra.

Wooden tit be really, really, REALLY nice if the map showed the roads instead of place names on a blank white sheet?