What is the difference between dysphasia and aphasia, or is it the same?

Partial vs. complete. aphasia refers to a complete inability to communicate due to brain injury, while dysphasia refers to a partial to complete inability. Both terms are used interchangeably. It could be due to any type of injury, from stroke to brain injury, to brain tumor. Usually involving the left side of the brain.
Different. By definition, dysphasia is difficulty speaking or problems with the speech. Dys = bad, phas = speech. Aphasia means inability to speak (either expressive or receptive). A = no, none.