What is meant by orphans?
It means that the block has no children blocks. (seriously, in bitcoin terminology, orphan == childless.. brilliant, isn't?
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Lol, indeed, ought be barren blocks.
I think the correct term is "invalid block"
also calling "transaction verification services" "mining" isn't terribly accurate
these are not Bitcoin terms so much as term that have been used by people in Bitcoin and adopted by others until it has become the common though confusing names we have today
For some time the generic name in my country for a 4 wheel drive vehicle was "Jeep" even though there are many 4wd vehicle manufacturers, no manufacturer apart from Jeep were happy with this - but it is still what we said - similar applies here