The word ‘dilate’ is usually heard in a health-care setting. When you visit an optometrist you may receive some drops in your eyes to dilate the pupils. The common man understands this is a verb, an action. It is to physically make something wider or larger.
A Candidate receiving his first instructions within the tyled recesses of a Masonic Lodge may simply accept that there is a further meaning. And indeed, when he explores this word with his sponsors and mentors he will learn that there is a further meaning.
As Masonry comes to us from an earlier age, an older meaning is intended of the word ‘dilate’ in our lectures. That meaning is to describe something, or to speak about something in detail and for a long time. Within the context of the lecture that deals with a virtue that is close to every Mason’s heart, it is hoped that the virtue is so well understood by the Candidate that we do not have to pause and give examples. Rather, we can immediately continue and see that virtue demonstrated by the Candidate.
The Master's Emblem Explained for Masons 