There is no exact synonym for "the".
In more ordinary contexts, an appropriate demonstrative pronoun -- one of "this", "that", "these", or "those" could usually be used instead of "the" and have almost the same meaning.
But in certain contexts, primarily legal ones, "said" can be used as a synonym for the.
For example, a patent claim might contain the phrase, "... a square rod, an electrical brush in contact with said square rod, ..." instead of "... a square rod, an electrical brush in contact with the square rod, ..." .
Murdered. Go to thesaurus.com to get more accurate answers next time