Having to do with one's office

formal, fitting, suitable, befitting, precise, established, ceremonious, according to precedent, according to protocol, proper, correct, accepted, recognized, customary; see also conventional 1, 2, 3, fit 1, 2.

Antonyms informal*, unceremonious*, ill-fitting.

Authorized

ordered, endorsed, sanctioned; see approved.

Reliable

authoritative, authentic, trustworthy, true, unquestionable, indubitable, veritable, real, sure, absolute, canonical, positive, clear, unequivocal, unmistakable, decisive, conclusive, unimpeachable, valid, authenticated, credible, bona fide, accurate, faithful, standard, irrefutable, incontestable, verified, proven, indisputable, not to be questioned, definite, assured, decided, to be depended on, to be trusted, worthy of confidence, undeniable, guaranteed, insured; see also certain 3, genuine 1, reliable 2.

Antonyms unreliable*, unauthentic, unverified.

Administrator

comptroller, director, executive; see administrator, leader 2.

A sports official

referee, umpire, judge, linesman, adjudicator, ref*, ump*, chain gang*; see also judge 2.