Dictionary
in•struc•tive
Pronunciation: (in-struk'tiv), [key]—
adj.
1. serving to instruct or inform; conveying instruction, knowledge, or information; enlightening.
2. Gram.noting a case, as in Finnish, whose distinctive function is to indicate means by which.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.