[thee-awr-boh] 
| an obsolete bass lute with two sets of strings attached to separate peg boxes, one above the other, on the neck. |
| the·or·bo (thē-ôr'bō) n. pl. the·or·bos A 17th-century lute having two sets of strings and an S-shaped neck with two sets of pegs, one set above and somewhat to the side of the other. [French théorbe, from Italian tiorba.] |
theorbo
large bass lute, or archlute, used from the 16th to the 18th century for song accompaniments and for basso continuo parts. It had six to eight single strings running along the fingerboard and, alongside them, eight off-the-fingerboard bass strings, or diapasons. Both sets of strings had separate pegboxes connected by an S curve in the instrument's neck. On 18th-century theorbos all but the two top courses of strings were double.
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