What does "slink" mean?

Additional senses

1. 2.To cast prematurely; -- said of female beasts; as, a cow that slinks her calf.
2. 3.Produced prematurely; as, a slink calf.
3. 4.Thin; lean. [Scot.]
4. 5.The young of a beast brought forth prematurely, esp. a calf brought forth before its time.
5. 6.A thievish fellow; a sneak. [Prov. Eng. & Scot.]