Synonyms:
periodic, periodical
Meaning: happening or recurring at regular intervals; "the periodic appearance of the seventeen-year locust"
Usage examples
William's bugle had just returned to public life after one of its periodic terms of retirement into his father's keeping.
It does not follow, however, that the peasant class was greatly affected by periodic revolutions of this kind, which brought little more to them than a change of rulers.
This is not a periodic disturbance, like the temporary acceleration of its motion discovered by Laplace, which in a few centuries, more or less, will be reversed; it is a disturbance which always acts one way, and which is therefore cumulative.
It is superposed upon all periodic changes, and, though it seems smaller than they, it is more inexorable. In a thousand years it makes scarcely an appreciable change, but in a million years its persistence tells very distinctly; and so, in the long run, the month is getting longer and the moon further off.
It is of the nature of a perturbation, and is therefore a periodic not a progressive or continuous change, and in a sufficiently long time it will be reversed. Still, for the last few thousand years the moon's motion has been, on the whole, accelerated (though there seems to be a very slight retarding force in action too).