“A “cowan” is a man with unlawful Masonic knowledge; an “intruder” is one with neither knowledge not secrets, who makes himself otherwise obnoxious; a “clandestine” is one who has been initiated by unlawful means, an “irregular” is one who has been initiated by a Lodge working without authorization.”.n other words, Lodge formed without a Warrant from the Grand Master (we now say Grand Lodge) is “clandestine,” and so a “clandestine Masons” is one made in a Lodge without a Warrant.”. Even this definition will not wholly serve; many old Lodges began and worked for a while without a Warrant yet were never Clandestine.