One who is “behind the times.”

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1890.  The women hurriedly retreated to their rooms at the hotel to escape curious eyes, for it was written all over us that we were, in Western terms “waybacks from wayback.”—Mrs. Custer, ‘Following the Guidon,’ p. 261 (N.Y.).

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1911.  Entering Mr. May’s quiet study I found him in intimate talk with a man of unassuming demeanor, in citizen’s dress, and marked by no distinction of face or figure. He might have been a delegate to a peace convention or a country minister from wayback calling on a professional brother. [This was Major-General Henry W. Slocum.]—N.Y. Ev. Post, Dec. 4, p. 6/2.

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