I realise that tea and teapots is not likely to be of interest to many over the pond, but perhaps the terminology may be common to other vessels.
I have quite a good teapot:-

It's a Le Creuset which is quite a good make, but, it suffers from a major fault. Tea leaks from the front of the lid as soon as you start to pour both when the pot is full and when the spout gets blocked by the tea bag.
I have seen pots with the following design change (I have just badly edited the picture):-

The lid has a complementary change: the lid is still round but the bit which projects into the opening is "just over semi-circular".
What is the name of this type of change so that I can search for one.
I've done searches for: teapot images, teapots with semi-circular lids and several others.
I found these
the anatomy of a teapot
teapot shapes
I thought this would be easy, but haven't found anything yet.
I suppose in desperation I could try to modify my existing pot.
Any ideas?
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