directive (adj.)

mid-15c., "pointing out the proper direction," from Medieval Latin directivus, from direct-, past-participle stem of Latin dirigere "to set straight" (see direct (v.)). From 1590s as "having the power of directing." From 1640s as a noun, "that which directs," a sense now obsolete; meaning "a general instruction how to proceed or act" is a modern use (1902).