In Christian art, an emblem of the Redeemer, called the “Lamb of God.” It is also the attribute of St. Agnes, St. Geneviève, St. Catherine, and St. Regina. John the Baptist either carries a lamb or is accompanied by one. It is also introduced symbolically to represent any of the “types” of Christ; as Abraham, Moses, and so on.
( The Vegetable) or Tartarian lamb; technically called Polypodium Barometz. It is a Chinese fern with a decumbent root, covered with a soft, dense yellow wool. Sir Hans Sloane, who calls it the Tartarian lamb, has given a print of it; and Dr. Hunter has given a print which makes its resemblance to a lamb still more striking. The down is used in India for staunching hæmorrhage.
Rooted in earth each cloven hoof descends, And round and round her flexile neck she bends; Crops the grey coral moss, and hoary thyme, Or laps with rosy tongue the melting rime; Eyes with mute tenderness her distant dam, And seems to bleat, a Vegetable Lamb.
Cold lamb. A schoolboy's joke. Setting a boy on a cold marble or stone hearth. Horace (Sat. i. 5, 22) has “Dotare lumbos,” which may have suggested the pun.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
More on Lamb from Fact Monster: