period
Pluralperiods
Pluralperiods
Formsperiods, perioding, perioded
- 1A stretch or length of time, especially one regarded as a single unit.
The factory shut down for a short period over the holidays.
Sales improved steadily over a six-month period.
UsageCommon with over, for and during: over a period of months, for a short period.
- 2A stretch of history, or of a person's life or career, regarded as a coherent whole with its own distinctive character.
The exhibition focuses on the Romantic period in European art.
Historians often divide the past into broad, named periods.
UsageUsually named by a word before it: the Victorian period, Picasso's Blue Period.
- 3Menstruation, or a single monthly occurrence of it, including the bleeding and the physical and emotional symptoms that accompany it.
Her period arrived a few days later than usual that month.
Some athletes track their periods to plan their training.
UsageUsually with a possessive: my period, her period. On your period means it is happening now.
Similarmenstruation
Note
A euphemism that works by naming only the time and leaving the rest unsaid.
Checked 2 Nov 2026 · 1 fact
- Period is a euphemistic term for menstruation, using the word for a stretch of time. en.wiktionary.org
- 4Each of the segments into which a school day is divided, each allotted to a subject or activity.
She teaches history during the first period of the morning.
Students change classrooms between periods.
UsageOften with a number and no article: in second period, first period is math.
Note
The word names the slot on the timetable rather than the lesson that fills it, which is why students move between periods.
- 5One of the set divisions of playing time that make up a game, such as the three periods in ice hockey, including any extra period played to break a tie.
The goalie made forty saves across all three periods.
They tied the game late in the second period.
Note
Ice hockey is the sport that has made this sense its own. A game typically runs in three periods, each named by its ordinal: the first period, the second, the last minute of the second period. When the score is still level at the end, play continues into an overtime period.
Checked 31 Oct 2026 · 2 facts
- An ice hockey game normally has three regulation periods. test.rulebook.iihf.com
- A game tied after regulation continues into overtime. iihf.com
- 6Used to emphasize that a statement is final and not open to further discussion.
We're leaving at noon, period.
She said no, and that settled it, period.
UsageComes at the end of a statement, often after a comma: the answer is no, period. It sounds firm, even curt.
Note
The punctuation mark spoken aloud, chiefly in Canadian and US English, and placed at the end of a statement to shut down argument. It borrows its force from the dot itself and sounds firm, even curt, so it suits insistence better than persuasion.
Checked 2 Nov 2026 · 1 fact
- The emphatic sense draws on the punctuation mark's function of ending a sentence. en.wiktionary.org
- 7Belonging to, or designed to evoke, a particular historical era, especially in style, costume, or setting.
The auction featured period weapons and military uniforms.
Their farmhouse is fitted with authentic period fixtures.
UsageUsually goes before a noun: period furniture, a period drama.
Similarhistorical
Oppositemodern, contemporary
Note
It can mean genuinely of the era or only made to look it, as with the costumes of a period drama.
- 8A unit of geologic time spanning millions to hundreds of millions of years, forming a subdivision of an era and itself divided into epochs.
The Cretaceous period ended about 66 million years ago.
Geologists date these fossils to the Devonian period.
Note
Geology makes a strict ladder of words that history treats as loose synonyms. In the historical sense, period, era and epoch can stand for one another. On the geologic time scale they are distinct ranks: an era is divided into periods, and a period into epochs.
Checked 2 Nov 2026 · 1 fact
- Era, period and epoch are distinct geological ranks, with periods subdividing eras and epochs subdividing periods. nacsn.americangeosciences.org
Less common meanings
- 9The punctuation mark “.”, used to end a sentence or to mark an abbreviation.
He always types a period followed by a single space.
Editors flagged every missing period in the manuscript.
UsageIn British English the mark is usually called a full stop.
Note
The North American and Philippine name for the dot that ends a sentence. Elsewhere the word has largely given way to another name. Zadie Smith's The Autograph Man (2002) turns the split into dialogue, as one character asks what 'the black spot at the end of a sentence' is called over there. The same dot gives American speech its emphatic 'end of story'.
Checked 31 Oct 2026 · 3 facts
- Zadie Smith wrote The Autograph Man. thebookerprizes.com
- The Autograph Man was first published in 2002. openlibrary.org
- The novel contains dialogue asking what the sentence-ending dot is called elsewhere, with the quoted wording. en.wiktionary.org
- 10The interval of time or length after which a regularly repeating phenomenon, function, or sequence returns to the same state; in mathematics, often the smallest such interval.
The period of Earth's rotation is about twenty-four hours.
Engineers carefully measured the period of the vibrating string.
Note
Here the Greek idea of a circuit is most literally alive. Something goes around and comes back, and the period is how long the round trip takes: one rotation of a planet, one repetition of a wave. In mathematics the repeating stretch need not be time at all: it may be an angle or a run of digits.
Checked 31 Oct 2026 · 5 facts
- The word's Greek ancestor includes the meaning “circuit”. en.wiktionary.org
- A period measures the time taken to complete a repeating cycle, including a wave cycle. openstax.org
- A planet's rotation period measures the time for one rotation. nssdc.gsfc.nasa.gov
- Mathematical periods need not measure time and can be angular intervals. en.wikipedia.org
- Periodicity can concern a repeating run of digits. en.wikipedia.org
- 11An end or conclusion; the point at which something finally stops, as in 'put a period to'.
My sufferings, physical and mental, are more than I can bear, and when such small arrangements as I have to make for your future well-being are completed it is my intention to put a period to them.
1886, H[enry] Rider Haggard, She: A History of AdventureNote
The image matches the punctuation mark: what the dot does to a sentence, this does to a quarrel, a hardship or a life. Its home is the phrase put a period to, as in Rider Haggard's She (1886–87): 'it is my intention to put a period to them.' The phrase usually stresses a deliberate act of stopping.
- 12A horizontal row in the periodic table of the elements.
Elements in the third period range from sodium to argon.
Moving across a period, atomic radius generally decreases.
Similarrow
Note
Chemistry takes the word from the repeating cycles that give the periodic table its name. Each row of the table is a period, referred to by ordinal number: the second period, the third period. The term applies only to the rows, which are read across the table, and never to its columns.
Checked 31 Oct 2026 · 3 facts
- Rows in the standard periodic table are numbered periods. en.wikipedia.org
- Periods run horizontally across the standard periodic table. periodic-table.rsc.org
- This needs qualification by layout: in Newlands' historical table, periods ran vertically and groups horizontally. en.wikipedia.org
- 13A specific moment during a given process; a point or stage reached within it.
The Death of Patroclus was the most eminent Period; and consequently the most proper Time for such Games.
1720, Alexander Pope, translating HomerNote
A point rather than a span, which is what makes it hard to read today. Pope, in a 1720 note to his translation of the Iliad, calls the death of Patroclus 'the most eminent Period', meaning the most notable moment and so the fittest time for funeral games. A modern reader expects a length of time and may misread the line. The sense is obsolete, and stage or point now does its job.
- 14The length of time a disease takes to run its full course, from onset to resolution.
Note
A word from older medicine, which spoke of a disease as having a span of its own to run through. The sense is obsolete, so readers meet it in old medical writing rather than in a modern clinic.
Checked 2 Nov 2026 · 2 facts
- Period historically meant the time a disease takes to run its course. en.wiktionary.org
- This medical sense is obsolete. en.wiktionary.org
- 15To come to an end, or to bring something to an end.
- 16To menstruate; to discharge blood and tissue from the uterus during the monthly cycle.
- 17A full sentence, particularly one that conveys a single idea or is built as a balanced, rhythmical unit.
- 18A musical unit consisting of two phrases, an antecedent and a consequent, that together form a complete idea.
- 19A Drosophila gene whose protein product helps regulate the circadian rhythm: the body's roughly 24-hour internal clock.
Showing meanings only.
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Origin
This word traces back to Ancient Greek 'períodos' ('circuit, orbit, a recurring interval of time'), from 'peri-' ('around') plus 'hodós' ('way'). It reached English through Medieval Latin 'periodus' and Middle French 'periode', eventually displacing native words like Middle English 'tide' and 'elde'.
Checked 31 Oct 2026 · 4 facts
- Period ultimately derives from Ancient Greek períodos, with the stated meanings. en.wiktionary.org
- The Greek word combines elements meaning around and way. en.wiktionary.org
- The transmission into English passed through Medieval Latin periodus and Middle French periode. en.wiktionary.org
- Period displaced native Middle English tide and elde in the relevant senses. en.wiktionary.org