Comfortable, yet unattractive, excessivly large, or otherwise stained underwear that is reserved for that special time of the month.
"Don't throw out those Vickies, they'll make great periodicals!"
by Eveal March 06, 2008
magazines or light reading
street newstands often sell periodicals
by Potipher the Prophet April 06, 2005
When a girl is pmsing due to her-time-of-the-month.
Man, you must be periodical or something, because your acting really bitchy.
by jojo_my_mojo October 17, 2008