1) or MacFadyen, Faden - (Ireland An Ulster name of both Irish and Scottish origin; without the prefix, the name is found in Mayo) Gules, three lions passant guardant in pale, per pale or and argent. Note: This is the O'Brien blazon. Historians are divided as to whether McFaddens or McFadyens use the O'Brien coat of Arms is appropriate.
2) or MacFadyen, Faden - Argent, two bends gules, in chief, a cock sable
3) or MacFadyen, Faden - Azure, a bend gules, three crosses pattee or.