prēˈskriptiv, prə̇ˈ-, -tēv also -təv adjective
Etymology: in sense 1, probably from prescript (II) + -ive; in other senses, from prescription, after such pairs as English description : descriptive
1. : serving to prescribe : laying down rules or directions : giving precise instructions
direct primary legislation is largely permissive rather than prescriptive — V.O.Key
traditional grammarians gave prescriptive rules of usage — A.S.Hornby
2. : acquired by, founded upon, or determined by prescription : established in or as if in law by immemorial use and enjoyment
the prescriptive rights and privileges of the nobles — Indian White Paper
our constitution is a prescriptive constitution — Edmund Burke
members of the upper chamber by prescriptive right
3. : arising from or recognized by long-standing custom : established by tradition or usage : customary
his prescriptive corner at the winter's fireside — Nathaniel Hawthorne
compliments to which there is no stated and prescriptive answer — Samuel Johnson
• pre·scrip·tive·ly -tə̇vlē adverb