What does "earmark" mean?

Earmark: A mark for identification; a distinguishing mark. Money is said to have no earmark. Wharton. Flying, he [a slave] should be described by the rounding of his head, and his earmark. Robynson (More's Utopia). A set of intellectual ideas . . . have earmarks upon them, no tokens of a particular proprietor. Burrow.

Additional senses

  1. 2.To mark, as sheep, by cropping or slitting the ear.

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