Like any legal document, the words of the Constitution mean the same thing today as they were understood to mean the moment it was ratified and given legal force.
For some of the text, definitions have changed significantly over time, and using a dictionary from that era is essential.
A commenter on our Facebook page is taking things in the right direction by suggesting this:
However, Bouvier’s wasn’t printed until 1839, much too late to be considered a resource for the framing of the Constitution decades earlier. But the Founders were all quite familiar with Giles Jacob’s law dictionary, which can be found here: