Authoritative Definition

endowed with authority sanctioned by established authority; "an authoritative communique"; "the authorized biography"

of or relating to the most highly developed stage of an earlier civilisation and its culture

clearly defined or formulated; "the plain and unequivocal language of the laws"- R.B.Taney of recognized authority or

of great significance or value; "important people"; "the important questions of the day" important in effect or meaning

having or exercising influence or power; "an influential newspaper"; "influential leadership for peace"

having official authority or sanction; "official permission"; "an official representative" of or relating to an office

conforming to or constituting a standard of measurement or value; or of the usual or regularized or accepted kind