DCHP-1 Online
flag day Northwest, Obs. 
one of certain specified days on which a river boat made stops for freight and passengers at points not on the regular schedule.
- 1916 Leaving the head of the lake about two in the afternoon, the journey is ended at eight, or a little later on "flag days."
- 1916 Leaving the head of the lake about two in the afternoon, the journey is ended at eight, or a little later on "flag days."