If you meant to type "metasie" but it appears to be a misspelling, there are a couple of possible correct suggestions. Perhaps you intended to write "metaside", which could refer to a side effect of a medication or a component of a chemical compound. Alternatively, you may have intended to write "metasize", which refers to the spread of cancer from its original site to other parts of the body. Double-check the context to determine the correct term.