tailpiece

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A piece forming an end; an appendage.
• noun Printing An engraving or design placed as an ornament at the end of a chapter or at the bottom of a page.
• noun Architecture A beam tailed into a wall.
• noun Music A triangular piece of ebony to which the lower ends of the strings of a violin or other related instrument are attached.

from The Century Dictionary.

• noun A piece forming a tail; a piece at the end; an appendage.
• noun In zoology, one of the parts or pieces composing the pygidium of an insect.

from the GNU version of the Collaborative International Dictionary of English.

• noun A piece at the end; an appendage.
• noun (Arch.) One of the timbers which tail into a header, in floor framing. See Illust. of Header.
• noun (Print.) An ornament placed at the bottom of a short page to fill up the space, or at the end of a book.
• noun A piece of ebony or other material attached to the lower end of a violin or similar instrument, to which the strings are fastened.
• noun (Locks) A piece for transmitting motion from the hub of a lock to the latch bolt.
• noun The part of a telescope containing the adjusting device for the eyepiece, etc.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun An appendage or appendix
• noun music A triangular piece of metal or ebony to which the strings of a violin, guitar, etc. are attached at the lower end
• noun architecture A short joist between a header and a wall

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun appendage added to extend the length of something