What is an eye formed in the bight or bend of a shroud or stay to go over the masthead; also, a rope to which certain parts of rigging, as dead-eyes, are secured called?

collar — (Naut.) An eye formed in the bight or bend of a shroud or stay to go over the masthead; also, a rope to which certain parts of rigging, as dead-eyes, are secured. (Webster's 1913.)

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