'To back an anchor' definitions:

Definition of 'To back an anchor'

From: GCIDE

Back \Back\ (b[a^]k), v. t. [imp. & p. p. Backed (b[a^]kt); p. pr. & vb. n. Backing.] [1913 Webster]
1. To get upon the back of; to mount. [1913 Webster]
I will back him [a horse] straight. --Shak. [1913 Webster]
2. To place or seat upon the back. [R.] [1913 Webster]
Great Jupiter, upon his eagle backed, Appeared to me. --Shak. [1913 Webster]
3. To drive or force backward; to cause to retreat or recede; as, to back oxen. [1913 Webster]
4. To make a back for; to furnish with a back; as, to back books. [1913 Webster]
5. To adjoin behind; to be at the back of. [1913 Webster]
A garden . . . with a vineyard backed. --Shak. [1913 Webster]
The chalk cliffs which back the beach. --Huxley. [1913 Webster]
6. To write upon the back of; as, to back a letter; to indorse; as, to back a note or legal document. [1913 Webster]
7. To support; to maintain; to second or strengthen by aid or influence; as, to back a friend. "The Parliament would be backed by the people." --Macaulay. [1913 Webster]
Have still found it necessary to back and fortify their laws with rewards and punishments. --South. [1913 Webster]
The mate backed the captain manfully. --Blackw. Mag. [1913 Webster]
8. To bet on the success of; -- as, to back a race horse. [1913 Webster]
To back an anchor (Naut.), to lay down a small anchor ahead of a large one, the cable of the small one being fastened to the crown of the large one.
To back the field, in horse racing, to bet against a particular horse or horses, that some one of all the other horses, collectively designated "the field", will win.
To back the oars, to row backward with the oars.
To back a rope, to put on a preventer.
To back the sails, to arrange them so as to cause the ship to move astern.
To back up, to support; to sustain; as, to back up one's friends.
To back a warrant (Law), is for a justice of the peace, in the county where the warrant is to be executed, to sign or indorse a warrant, issued in another county, to apprehend an offender.
To back water (Naut.), to reverse the action of the oars, paddles, or propeller, so as to force the boat or ship backward. [1913 Webster]