Homonyms, homographs, homophones, heteronyms… 

This one rewards a little close attention—looking at each of the words and figuring out their different meanings or sounds.

I’ve always loved heteronyms and how we can have a single word spelt the same and yet pronounced quite differently — like read — and how that clearly makes English a crazy language to learn. And, as you probably do too, I pretty much woke up at night thinking how you could sort words into groups of the same or different spelling and the same or different sounds and begin to make sense of these curious groups of words like homographs, homophones and heteronyms.

Words with different spellings and different sounds generally just mean different words.

There are nice buckets of other words too like contranyms — words that can be their own opposite. And also aptronyms.

I did think a third axis of the same or different meaning may give the complete picture but would probably just serve to confuse things.

Some Greek: homo—same, hetero—different, graph—written, phone—sound