a. [ Cf. F. instrumental. ] [ 1913 Webster ] 1. Acting as an instrument; serving as a means; contributing to promote; conductive; helpful; serviceable; as, he was instrumental in conducting the business. [ 1913 Webster ] The head is not more native to the heart,
The hand more instrumental to the mouth. Shak. [ 1913 Webster ] 2. (Mus.) Pertaining to, made by, or prepared for, an instrument, esp. a musical instrument; as, instrumental music, distinguished from vocal music. “He defended the use of instrumental music in public worship.” Macaulay. [ 1913 Webster ] Sweet voices mix'd with instrumental sounds. Dryden. [ 1913 Webster ] 3. (Gram.) Applied to a case expressing means or agency; as, the instrumental case. This is found in Sanskrit and Russian as a separate case, but in Greek it was merged into the dative, and in Latin into the ablative. In Old English it was a separate case, but has disappeared, leaving only a few anomalous forms. [ 1913 Webster ]
Instrumental errors, those errors in instrumental measurements, etc., which arise, exclusively from lack of mathematical accuracy in an instrument. [ 1913 Webster ]
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