Does "What does this mean?" refer to the definition of a word (such as "What does the word 'cake' mean?") or is it referring to a consequence or significance (such as "Look at this cake! What could this mean?")?
Could be either but if you're just referring to one word, you'd probably prefer to say det här ordet 'this word'. So most likely either the latter or the meaning of a phrase, sentence or larger chunk of text.