Emily Dickinson Lexicon

CIR'CU-LAR, a. [L. circularis. See Circle.]

1. In the form of a circle; round; circumscribed by a circle; spherical; as, the sun appears to be circular.
2. Successive in order; always returning. – Roscommon.
3. Vulgar; mean; circumforaneous; as, a circular poet. – Dennis.
4. Ending in itself; used of a paralogism, where the second proposition at once proves the first, and is proved by it. – Johnson. Baker.
5. Addressed to a circle, or to a number of persons having a common interest; as, a circular letter.
6. Circular lines, such straight lines as are divided from the divisions made in the arch of a circle; as, the lines of sines, tangents and secants, on the plain scale and sector. Johnson.
7. Circular numbers, are those whose powers terminate in the roots themselves; as 5 and 6, whose squares are 25 and 36. – Bailey.
8. Circular sailing, is the method of sailing by the arch of a great circle. – Encyc.