Emily Dickinson Lexicon

PE-RI-OD'IC, or PE-RI-OD'IC-AL, a. [It. periodico; Fr. periodique.]

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. – Watts.
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. – Addison.
5. Pertaining to a period; constituting a complete sentence. – Adam's Lect.
6. Pertaining to a revolution or regular circuit. – Brown.