A similar term related to bitcoin orphan blocks is referred to as Uncle Blocks. Uncle blocks are to ethereum as orphan blocks are to bitcoin. Just like the way orphan blocks are validated, mined without getting added to the blockchain genuinely is how uncle blocks work on Ethereum blockchain too. They are caused by the blockchain working mechanism.
When transactions are validated and mined by miners securing the ethereum blockchain network, they are added as the new blocks which keep forming the growing blockchain network. But sometimes delay happens on the network which causes more than one miner solving for the same block and tries to add it to the network. The one that has a lower share of proof of work is the uncle blocks which wont be added to the network. It is also important to know that ethereum blockchain rewards uncle blocks miners while bitcoin blockchain doesn't reward orphan blocks miners.