VIOLONCELLO (Fr. violoncelle, Ger. Violoncell, Ital. violoncello)  , the bass member of the violin family . Although the word violoncello is a diminutive, signifying " small violone," or double bass, the instrument is really a bass violin, formed on a different model from the violone, which has the sloping shoulders and flat back of the viol family, whereas those of the violoncello are rounded as in the violin . The construction of the violoncello is therefore the same as that of the violin (q.v.) but on a much larger scale . It is either held, on account of its size, between the performer's knees, or rests on the floor supported on a foot or spike .