once and again

Webster's Dictionary (GCIDE)

Once \Once\ (w[u^]ns), adv. [OE. ones, anes, an adverbial form fr. one, on, an, one. See One-, -Wards.]

1.For one time; by limitation to the number one; not twice nor any number of times more than one. [1913 Webster]

Ye shall . . . go round about the city once.— Josh. vi. 3.[1913 Webster]

Trees that bear mast are fruitful but once in two years.— Bacon.[1913 Webster]

2.At some one period of time; -- used indefinitely. [1913 Webster]

My soul had once some foolish fondness for thee.— Addison.[1913 Webster]

That court which we shall once govern.— Bp. Hall.[1913 Webster]

3.At any one time; -- often nearly equivalent to ever, if ever, or whenever; as, once kindled, it may not be quenched. [1913 Webster]

Wilt thou not be made clean? When shall it once be?— Jer. xiii. 27.[1913 Webster]

To be once in doubt Is once to be resolved.— Shak.[1913 Webster]

Note: Once is used as a noun when preceded by this or that; as, this once, that once. It is also sometimes used elliptically, like an adjective, for once-existing. "The once province of Britain." --J. N. Pomeroy. [1913 Webster]

At once. (a) At the same point of time; immediately; without delay. "Stand not upon the order of your going, but go at once." --Shak. "I . . . withdrew at once and altogether." --Jeffrey. (b) At one and the same time; simultaneously; in one body; as, they all moved at once.

Once and again, once and once more; repeatedly. "A dove sent forth once and again, to spy." --Milton. [1913 Webster]