in·stru·men·tal /ˌɪn(t)strəˈmɛntḷ/ 形容詞
1. Acting as an instrument; serving as a means; contributing to promote; conductive; helpful; serviceable; as, he was instrumental in conducting the business.
The head is not more native to the heart,
The hand more instrumental to the mouth. --Shak.
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.”
Sweet voices mix'd with instrumental sounds. --Dryden.
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.
Instrumental errors, those errors in instrumental measurements, etc., which arise, exclusively from lack of mathematical accuracy in an instrument.
adj 1: relating to or designed for or performed on musical
instruments; "instrumental compositions"; "an
instrumental ensemble" [ant: vocal]
2: serving or acting as a means or aid; "instrumental in
solving the crime" [syn: implemental]