The really impossible thing to translate into English here is that 道 was also the verb “to say.” So 道可道 is a pun that could mean “the way that can be trod” or “

The really impossible thing to translate into English here is that 道 was also the verb “to say.” So 道可道 is a pun that could mean “the way that can be trod” or “the way that can be said.”