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Related to periodic: periodic table, periodic wave, Periodic signal


repeated or recurring at intervals.
periodic fever a hereditary condition characterized by repetitive febrile episodes and systemic symptoms, occurring in precise or irregular cycles of days, weeks, or months. See also familial periodic fever.


1. Recurring at regular intervals.
2. Denoting a disease with regularly recurring exacerbations or paroxysms.
3. Denoting any of several oxoacids of iodine.


/pe·ri·od·ic/ (pēr´e-od´ik)
1. recurring at regular intervals of time.
2. recurring intermittently or occasionally.


Etymology: Gk, peri + hodos, way
(of an event or phenomenon) recurring at regular or irregular intervals. periodicity, n.


1. Recurring at regular intervals.
2. Denoting a disease with regularly recurring exacerbations or paroxysms.


repeated or recurring at intervals.

periodic acid-Schiff stain (PAS)
periodic acid followed by Schiff reagent stains polysaccharides, glycoproteins and glycolipids. It is used to demonstrate fungal elements.
periodic breathing
alternating periods of apnea and hyperventilation. See also biot's respirations, cheyne-stokes respiration.
inherited periodic spasticity
a defect in cattle which does not appear until they are adults. On rising from a recumbent position the hindlimbs are extended and the animal is unable to flex them. Spasticity may last for 15 minutes but the patient will eventually relax and walk normally. Causes inconvenience only. Called also stall-cramp, the stretches.
periodic movement
periodic myelodysplasia
see canine cyclic hematopoiesis.
periodic ophthalmia
see periodic ophthalmia.
periodic reassessment
re-examination at intervals of registered veterinarians to ensure their continued educational refreshment. Adequate performance obligatory for reregistration.

Patient discussion about periodic

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 periodic
References in periodicals archive ?
The Koleos is available with free registration, free unlimited warranty period of up to six years free registration, free periodic maintenance service up to two years/3,000km (whichever comes first) and a cash gift of RO250.
The New Science of Cosmology Newsletter discusses 2 new Galaxy Periodic Tables of Anti-Matter and Matter that parallel Chemistry's 2 Element Periodic Tables.
We use the symbol of periodic cyclic alternate reverse sequence to write out the odd-periodic sequence a (n) of odd sequence a (n): [?
In his preface the author states that he aims first of all to develop a mathematical framework for analyzing wave processes involved in periodic structures and, secondly, to show that existing classical electromagnetism (e.
7%) of 41 children who received SSRIs at the time of the study experienced periodic limb movements of sleep, vs.
According to the data provided by Nuclear Periodic Table [1], all spectacularity of the data was split into blocks, wherein the number of isotopes was determined, namely: 431 (s), 1277 (p), 1612 (d), 1147 (f).
About the only things we can drop in front of them and be sure they'll grasp are numbers like pi and the periodic table.
The Periodic Table of chemistry is a tabular arrangement of the chemical elements according to atomic number, as based on the Periodic Law which states that certain properties of elements repeat periodically when arranged by periodic number.
According to the terms of the contract, the French firm would supply its mobile testing stations for periodic checking of automobile vehicles in Saudi Arabia.
This book delves into the theoretical design, fabrication, and practical applications of nano and micro scale periodic materials.
In [5] the author studied the existence of periodic solutions of the Volterra difference system with infinite delay