Periods

noun

1. A length of time.

   "There was a period of confusion following the announcement."

2. A period of time in history seen as a single coherent entity; an epoch, era.

   "Food rationing continued in the post-war period."

3. The punctuation mark “.” (indicating the ending of a sentence or marking an abbreviation).
4. The length of time during which the same characteristics of a periodic phenomenon recur, such as the repetition of a wave or the rotation of a planet.
5. Female menstruation.

   "When she is on her period, she prefers not to go swimming."