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recurrence at regular intervals of time.


Tendency to recur at regular intervals.


/pe·ri·o·dic·i·ty/ (pēr″e-ah-dis´ĭ-te) recurrence at regular intervals of time.


Etymology: Gk, periodikos, periodical
events or episodes that tend to repeat at predictable intervals. For example, filarial worms may appear in cutaneous blood vessels at night but not in daylight hours, and malaria may cause paroxysms at 24-, 48-, or 72-hour intervals, depending on the species of pathogen.


Tendency to recurrence at regular intervals.


1. Recurring at intervals or in cycles.
2. Of DNA, the number of base pairs in one complete turn of the double helix. The periodicity of DNA is about 10.


  1. the carrying out of certain functions on a regular basis.
  2. the interval between two peaks of activity in a cyclic process.
  3. the number of base pairs per turn of the double helix in DNA.


n the quality of being periodic or recurring at definite intervals of time.


Tendency to recur at regular intervals.


recurrence at regular intervals of time.

circadian periodicity
every 24 hours.
diurnal periodicity
twice daily.

Patient discussion about periodicity

Q. i just have my period last november 25 and ended on 28.when is my possible fertile and ovulation period please help me identify my fertile and ovulation period

A. If someone knew it, it'd solve the human race many problems with fertility. The problem is that ovulation (and thus, the period of possible fertility) happens 14 days BEFORE the onset of menses, so you know about it only retrospectively.

However there ways such as serial body temperature measuring, along with kits that measures the level of hormones in the urine in order to estimate the time of the coming ovulation, and help in timing intercourse.

You may read more about it here ( ) but anyway, consulting a doctor (e.g. gynecologist) may be wise.

Q. can you get pregnant on your period? i know that you get pregnant when you ovulate and you ovulate in the middle of your menstration cycle, but people have told me that you can get pregnant on your period. can somebody help me out???

A. It's possible, if your menses are long enough and your period is short enough, since semen can survive (and fertilize the ova) up to 3 days after intercourse. It's not common, but also not impossible. That's why the safe-days method isn't very effective in preventing pregnancy.

Q. how should i support my wife during this tough period?

A. first of all don't call it a tough period. a happy period might work better. although the wife can get annoyed by it. but she'll get annoyed from anything... just try to make her comfortable. foot massage , bubble baths, movies and popcorn.
it really depends on what kind of person is she and what she likes or not.


More discussions about periodicity
References in periodicals archive ?
The 4th edition of Bright Futures will include another freshly updated periodicity schedule that likely will include maternal depression screening and a recommendation for developmental screening at 4 years, as well as an expanded window for HIV testing from the current 16-18 years to 15-21 years, said Dr.
Although some information exists on the diet composition of all four of the cyprinid species examined in the Salmon River, little is known about diel variation in diet composition and feeding periodicity.
The recruit numbers (oysters <25 mm) time series shows a significant periodicity at 4 y as well as at 1 y (Fig.
n] where a > 0, and n is a natural number gives a positive or negative value with a periodicity of 2.
First, we estimate almost periodicity regulator of S.
When the distance of the sensor node is increased, we can see that, the deep fade or periodicity shifts to the higher frequency band.
There are natural sources of tiling periodicity when considering multidimensional [n.
present recent methods of study on the asymptotic behavior of solutions of abstract differential equations in Banach spaces, such as stability, exponential dichotomy, periodicity, almost periodicity, and almost automorphy of solutions.
Data from Greenland proves that the current warm period "corresponds to a cyclic warming peak within a ~1500 year periodicity of probable solar origin .
If you erase the data by whatever means, you should see a surface devoid of any specific pattern or periodicity," says Michael Knotts of the GTRI.
The pandemic had appeared exactly 10 years after appearance of the A' virus, which suggested pandemic periodicity (5).
Following successful quantification and removal of the barometric effects on water-level data, the residual hydrographs suggested an additional, smaller amplitude periodicity was still present in the water-level records.