Acting as an instrument; serving as a
means; contributing to promote; conductive; helpful; serviceable; as,
he was instrumental in conducting the business.
Pertaining to, made by, or
prepared for, an instrument, esp. a musical instrument; as,
instrumental music, distinguished from vocal
music.
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.
In celebration of Noah Webster's Birthday (October 16, 2009), we have prepared an updated website. 
