The word "Guiser" refers to someone who wears a disguise or costume, especially on festive occasions. Some synonyms for this word include masquerader, costumed reveler, fancy-dresser, mummer, and illusionist. A masquerader is someone who wears a mask or disguise to conceal their identity, while a costumed reveler is someone who dresses up in a costume or fancy dress to celebrate an event. A fancy-dresser, on the other hand, is someone who enjoys dressing up in extravagant or unusual clothes. A mummer is a performer who wears a mask and performs a traditional play or dance, while an illusionist is someone who creates illusions or tricks using sleight of hand.