Are contemporary homes or Modern designs considered Period work?

Let's begin with the first few entries of the definition of ' period':

1.
a rather large interval of time that is meaningful in the life of a person, in history, etc., because of its particular characteristics: a period of illness; a period of great profitability for a company; a period of social unrest in Germany.
2.
any specified division or portion of time: poetry of the period from 1603 to 1660.
3.
a round of time or series of years by which time is measured.
4.
a round of time marked by the recurrence of some phenomenon or occupied by some recurring process or action.
5.
the point of completion of a round of time or of the time during which something lasts or happens.

If a style of architecture (or art) shows a distinct characteristic in form and material use, or process of construction that can be identified within a specific period of time then it can be categorized and termed 'of the period ca. ____'. Religious, philosophical, scientific and cultural changes and advances also were classified into movements. All styles, made up of specific characteristics, can be termed 'period' including Bauhaus Modern, Deconstructive, Beaux Arts, Gothic Perpendicular, Louis XIV, Post Modern, Art Deco etc. Regional styles like 'California contemporary' or 'Florida Mediterranean' are examples in flux and too general to categorize. Architects can create a revival of architecture that is merely one or two years old if distinct and superceded by another one that breaks the previous characteristic elements.