What does "single" mean?

Additional senses

1. 2.Hence, unmarried; as, a single man or woman. Grows, lives, and dies in single blessedness. Shak. Single chose to live, and shunned to wed. Dryden.
2. 3.Not doubled, twisted together, or combined with others; as, a single thread; a single strand of a rope.
3. 4.Performed by one person, or one on each side; as, a single combat. These shifts refuted, answer thy appellant, . . . Who now defles thee thrice ti single fight. Milton.
4. 5.Uncompounded; pure; unmixed. Simple ideas are opposed to complex, and single to compound. I. Watts.
5. 6.Not deceitful or artful; honest; sincere. I speak it with a single heart. Shak.
6. 7.Simple; not wise; weak; silly. [Obs.] He utters such single matter in so infantly a voice. Beau & Fl. Single ale, beer, or drink, small ale, etc., as contrasted with double ale, etc., which is stronger. [Obs.] Nares. -- Single bill (Law), a written engagement, generally under seal, for the payment of money, without a penalty. Burril. -- Single court (Lawn Tennis), a court laid out for only two players. -- Single-cut file. See the Note under 4th File. -- Single entry. See under Bookkeeping. -- Single file. See under 1st File. -- Single flower (Bot.), a flower with but one set of petals, as a wild rose. -- Single knot. See Illust. under Knot. -- Single whip (Naut.), a single rope running through a fixed block.
7. 8.To select, as an individual person or thing, from among a number; to choose out from others; to separate. Dogs who hereby can single out their master in the dark. Bacon. His blood! she faintly screamed her mind Still singling one from all mankind. More.
8. 9.To sequester; to withdraw; to retire. [Obs.] An agent singling itself from consorts. Hooker.
9. 10.To take alone, or one by one. Men . . . commendable when they are singled. Hooker.
10. 11.To take the irrregular gait called single-foot;- said of a horse. See Single-foot. Many very fleet horses, when overdriven, adopt a disagreeable gait, which seems to be a cross between a pace and a trot, in which the two legs of one side are raised almost but not quite, simultaneously. Such horses are said to single, or to be single-footed. W. S. Clark.
11. 12.A unit; one; as, to score a single.
12. 13.pl. The reeled filaments of silk, twisted without doubling to give them firmness.
13. 14.A handful of gleaned grain. [Prov. Eng. & Scot.]
14. 15.(Law Tennis) A game with but one player on each side; -- usually in the plural.
15. 16.(Baseball) A hit by a batter which enables him to reach first base only.