An instrument is a concrete or abstract tool intended for a purpose other than mechanical work, in particular a refined one.
Musical instruments are devices designed to produce music, frequently by plucking or striking a string or bell or drum surface, or by forcing air to resonate (see wind instruments).
... to serve eight-year terms; one-third elected after a four-year period, two-thirds elected after the next four-year period. Beside the Senate there is the Chamber of ...