What does "again" mean?

Additional senses

1. 2.3. Once repeated; -- of quantity; as, as large again, half as much again.
2. 3.In any other place. [Archaic] Bacon.
3. 4.On the other hand. "The one is my sovereign . . . the other again is my kinsman." Shak.
4. 5.Moreover; besides; further. Again, it is of great consequence to avoid, etc. Hersche Again and again, more than once; often; repeatedly. -- Now and again, now and then; occasionally. -- To and again, to and fro. [Obs.] De Foe. Note: Again was formerly used in many verbal combinations, as, again- witness, to witness against; again-ride, to ride against; again-come, to come against, to encounter; again-bring, to bring back, etc.
5. 6.Against; also, towards (in order to meet). [Obs.] Albeit that it is again his kind. Chaucer.