decachord

from The Century Dictionary.

• noun A musical instrument with ten strings; specifically, an obsolete French musical instrument of the guitar class having ten strings.
• noun . Something consisting of ten parts; a bundle consisting of ten things bound, as it were, together.

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

• noun An ancient Greek musical instrument of ten strings, resembling the harp.
• noun Something consisting of ten parts.

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

• noun An Ancient Greek musical instrument with ten strings, resembling the harp.