Interval of time.
Related information about period:
- Period - Wikipedia, the free encyclopedia
 Period (from Greek περίοδος) or periodic may refer to: Timeframe, a length or era   of time; Full stop, also called a period – a dot at the end of a sentence ...
 
- Orbital period - Wikipedia, the free encyclopedia
 The orbital period is the time taken for a given object to make one complete orbit   about another object. When mentioned without further qualification in ...
 
- Menstrual cycle - Wikipedia, the free encyclopedia
 The cessation of menstrual cycles at the end of a woman's reproductive period is   termed menopause. The average age of menopause in women is 52 years, ...
 
- Coping With Common Period Problems
 Most girls have to deal with PMS, cramps, or headaches around the time of their   periods. These problems are usually nothing to worry about. Get the facts on ...
 
- period - Wiktionary
 period (not comparable) ... As the guests arrived — there were about a hundred,   a majority in period attire — I ... Food rationing continued in the post-war period.
 
- The Period
 Use a period [ . ] at the end of a sentence that makes a statement. There is no   space between the last letter and the period. Use one space between the period ...
 
- xkcd: Period
 Image URL (for hotlinking/embedding): http://imgs.xkcd.com/comics/period.png.   Voice: Ugh. Stupid uterus. Man: Hey, your period is every 28 days, right?
 
- Period - Definition and More from the Free Merriam-Webster Dictionary
 the completion of a cycle, a series of events, or a single action : conclusion. 2. a (  1) : an utterance from one full stop to another : sentence (2) : a ...