Noah Webster
Periodic
PERIOD'IC
PERIOD'ICAL, adjective
1. Performed in a circuit, or in a regular revolution in a certain time, or in a series of successive circuits; as the periodical motion of the planets round the sun; the periodical motion of the moon round the earth.
2. Happening by revolution, at a stated time; as, the conjunction of the sun and moon is periodical.
3. Happening or returning regularly in a certain period of time. The Olympiads among the Greeks were periodical, as was the jubilee of the Jews.
4. Performing some action at a stated time; as the periodical fountains in Switzerland, which issue only at a particular hour of the day.
5. Pertaining to a period; constituting a complete sentence.
6. Pertaining to a revolution or regular circuit.