Definitions of instrumental

1. Instrumentality.

2. serving or acting as a means or aid; " instrumental in solving the crime"

3. Helpful.

4. Pertaining to, made by, or prepared for, an instrument, esp. a musical instrument; as, instrumental music, distinguished from vocal music.

5. Applied to a case expressing means or agency; as, the instrumental case. This is found in Sanskrit 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.

6. Pertaining to, or done by, an instrument; helping to bring about some end; helpful.

7. Acting as an instrument or means: serving to promote an object: helpful: belonging to or produced by musical instruments.

8. Acting as an instrument; conducive; produced by instruments.

9. Fitted for or played upon musical instruments.

10. Conducive, as an instrument or means, to some end; pertaining to music arising from instruments, as instrumental music.

11. Pert. to an instrument; serving to promote or effect some object; not vocal, as instrumental music.