period

Definitions

• A length of time.
• A period of time in history seen as a single coherent entity; an epoch, era.
• (now) The punctuation mark “.” (indicating the ending of a sentence or marking an abbreviation).
• 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.
• Female menstruation.
• A section of an artist's, writer's (etc.) career distinguished by a given quality, preoccupation etc.
• Each of the divisions into which a school day is split, allocated to a given subject or activity.
• (chiefly) Each of the intervals into which various sporting events are divided.
• (obsolete) The length of time for a disease to run its course.
• An end or conclusion; the final point of a process etc.
• (rhetoric) A complete sentence, especially one expressing a single thought or making a balanced, rhythmic whole.
• (obsolete) A specific moment during a given process; a point, a stage.
• (chemistry) A row in the periodic table of the elements.
• (geology) A subdivision of an era, typically lasting from tens to hundreds of millions of years, see _Appendix: Geologic timescale.
• (genetics) A Drosophila gene, the gene product of which is involved in regulation of the circadian rhythm.
• (music) Two phrases (an antecedent antecedent and a consequent consequent phrase).
• (math) The length of an interval over which a periodic function, periodic sequence or repeating decimal repeats; often the least such length.
• (archaic) End point, conclusion.