- 1A length or portion of time: he had long periods of depression the period 1977–85 the training period is between 16 and 18 monthsMore example sentences
- The fluvial sediments, however, represent rapid deposition in relatively short periods (days or months).
- Hauling and applying manure may require large blocks of time for relatively short periods throughout the year.
- Generally, consumers have accepted the relatively short periods of 14 to 21 days for half or full gallons of milk.
- 1.1A portion of time in the life of a nation, civilization, etc. characterized by the same prevalent features or conditions: the early medieval periodMore example sentences
- Life at the bottom of society was always difficult in the late medieval and early modern periods: but around 1600 conditions for many of the poor were terrible.
- His work has focused on the medieval and early modern periods.
- Of these, 98 per cent cover the 19th and 20th centuries, while only 16 per cent cover medieval or earlier periods.
- 1.2A major division of geological time that is a subdivision of an era and is itself subdivided into epochs: the Cretaceous periodMore example sentences
- Because of this, clay becomes progressively less common in older geological periods and is almost never found in Precambrian formations.
- The following table shows the three eras and eleven geological periods that comprise the Phanerozoic.
- This book shows the dynamic effects of the many periods of Pleistocene glacial advance and melting on the geology and topography of the northwestern United States.
- 1.3Each of the set divisions of the day in a school allocated to a lesson or other activity: two periods of PE are allocated on the timetable he interviewed the teachers when they had a free periodMore example sentences
- I would look at it later and make sense of it but, as for now, I had to get to my next lesson because the free period would probably be nearing an end.
- The total lesson takes several class periods and I recite the poems to motivate my young artists many times throughout the lesson.
- To accommodate the rich level of activity hoped for in his mathematical laboratory, he proposed that two consecutive class periods be allocated to it.
- 1.4Each of the divisions of the playing time of a sporting event: the Lightnings ran at the Leafs hard in a very rough first periodMore example sentences
- In the first period of extra time both teams played at a frenetic pace with tenacious defending keeping Keighley's hopes alive.
- There is an extra period called injury time, usually in the vicinity of three minutes.
- If games are tied at full-time an extra period will be played with the first team to score winning the game.
- 2 Physics The interval of time between successive occurrences of the same state in an oscillatory or cyclic phenomenon, such as a mechanical vibration, an alternating current, a variable star, or an electromagnetic wave.More example sentences
- To produce a larger effect, the motion must accumulate, and for wave-impulses to accumulate, they must arrive in periods identical with the periods of vibration of the atoms on which they impinge.
- 2.1 Astronomy The time taken by a celestial object to rotate about its axis, or to make one circuit of its orbit.More example sentences
- The atmosphere rotates with periods ranging from over 18 hours near the equator to faster than 13 hours near the poles.
- In contrast, Jupiter-family comets tend to have predictable, well-determined orbits with short periods and low inclinations.
- The first problem Galileo attacked at Florence was to determine orbits and periods for Jupiter's four satellites.
- 2.2 Mathematics The interval between successive equal values of a periodic function.More example sentences
- What is the period of the continued fractions of the following numbers?
- In 1834 Jacobi proved that if a single-valued function of one variable is doubly periodic then the ratio of the periods is imaginary.
- 3 (also menstrual period) A flow of blood and other material from the lining of the uterus, lasting for a few days and occurring in sexually mature women who are not pregnant at intervals of about one lunar month until the menopause: she’s got her period [as modifier]: period painsMore example sentences
- It is common to have heavy blood flow at the beginning of a period and lighter blood flow at the end.
- It mostly affects women between the ages of 50 and 70, who have been through the menopause (when your periods stop).
- Women may also experience painful periods and pain during sexual intercourse.
- 4.1 • informal , chiefly North American Added to the end of a statement to indicate that no further discussion is possible or desirable: he is the sole owner of the trademark, period
- 5 Chemistry A set of elements occupying a horizontal row in the periodic table.More example sentences
- The horizontal rows or periods also have predictable trends in characteristics because as you move left to right in a row only one electron is added changing the atomic number by one.
- As we move down the periods, the elements have a greater atomic weight.
- 6 Rhetoric A complex sentence, especially one consisting of several clauses, constructed as part of a formal speech or oration.More example sentences
- There is frequently poor closure of periods and an inept employment of rhythm in the closure of stanzas and of poems.
- 6.1 Music A complete idea, typically consisting of two or four phrases.More example sentences
- His's an oceanic performance that gives emphasis to the work's undulating hemiolas as they reach across bar lines and destabilize phrase periods.
adjective[attributive] Back to top
- Belonging to or characteristic of a past historical time, especially in style or design: an attractive and beautifully modernized period house a splendid selection of period furnitureMore example sentences
- This house is a great blend of period qualities and contemporary design.
- One of the highlights of the weekend will be period re-enactments of historical trials in the old Law Courts in City Hall.
- A home that has both period style and modern comforts - is it perfection?
put a period to
- • dated Put an end to: in dry climates, the onset of summer drought may put a period to plant activityMore example sentences
- ‘They say they want to put a period to my presidency.’
- Then there's a lull; people stare into their empty glasses, then pat the table with open palms and put a period to our merry night.
- Plot had not originally intended to include such material in the book since he believed that the chapter on arts had ‘finish'd the Natural History of Oxford-shire’ and prompted him ‘accordingly [to] here put a period to my Essay!’
late Middle English (denoting the time during which something, especially a disease, runs its course): from Old French periode, via Latin from Greek periodos 'orbit, recurrence, course', from peri- 'around' + hodos 'way, course'. The sense 'portion of time' dates from the early 17th century.