violone

[vee-uh-loh-ney] /ˌvi əˈloʊ neɪ/
noun
1.
a double bass.
2.
an organ pedal stop of 16-foot pitch, giving a tone resembling the violoncello.
Origin
1715-25; < Italian, equivalent to viol(a) bass viol + -one augmentative suffix
British Dictionary definitions for violone

violone

/ˈvaɪəˌləʊn/
noun
1.
the double-bass member of the viol family lying an octave below the viola da gamba. It corresponds to the double bass in the violin family
Word Origin
C18: from Italian, from viola1 + -one, augmentative suffix