The Latin passus meant pace, step, track, passage; it contains the picture of a path, road, aisle, or door through which one can make his way, hence our “pass,” derived from it. From it also we have our word “pace.” A password is any agreed word or counter-sign that permits one to pass through an en-trance or passage otherwise closed.
- Source: 100 Words in Masonry
A word intended, like the military countersign, to prove the friendly nature of him who gives it, and is a test of his right to pass or be admitted into a certain place. Between a Word and a Password there seems fo be this difference: the former is given for instruction, as it always contains a symbolic meaning; the latter, for recognition only. Thus, the author of the life of the celebrated Elias Ashmole says, "Freemasons are known to one another all over the world by certain passwords known to them alone; they have Lodges in different countries, where they are relieved by the brotherhood if they are in distress".
- Source: Mackey's Encyclopedia of Freemasonry