THESAURUS
Opportune
a propos, ad rem, adapted, advantageous, advisable, applicable, apposite, appropriate, apropos, apt, auspicious, becoming, befitting, beneficial, congruous, convenient, decent, desirable, dovetailing, expedient, favorable, feasible, felicitous, fit, fitted, fitten, fitting, fortunate, fructuous, geared, germane, good, happy, helpful, just right, likely, lucky, meet, meshing, on the button, pat, pertinent, politic, profitable, proper, propitious, prosperous, providential, qualified, recommendable, relevant, right, ripe, seasonable, seemly, sortable, suitable, suited, suiting, tailored, timely, to be desired, to the point, to the purpose, useful, well-timed, wise, worthwhile
ROGET THESAURUS
Opportune
Expedience
N
expedience, expediency, desirableness, desirability, fitness, utility, propriety, opportunism, advantage, high time, expedient, desirable, advisable, acceptable, convenient, worth while, meet, fit, fitting, due, proper, eligible, seemly, becoming, befitting, opportune, in loco, suitable, applicable, in the right place, conveniently, operae pretium est.
Occasion
N
timeliness, occasion, opportunity, opening, room, event (eventuality), suitable season, proper season, suitable time, proper time, high time, opportuneness, tempestivity, crisis, turn, juncture, conjuncture, crisis, turning point, given time, nick of time, golden opportunity, well timed opportunity, fine opportunity, favorable opportunity, opening, clear stage, fair field, mollia tempora, fata Morgana, spare time, opportune, timely, well-timed, timeful, seasonable, providential, lucky, fortunate, happy, favorable, propitious, auspicious, critical, suitable, obiter dicta, opportunely, in proper course, in due course, in proper season, in due season, in proper time, in due time, for the nonce, in the nick of time, in the fullness of time, all in good time, just in time, at the eleventh hour, now or never, by the way, by the by, en passant, a propos, pro re nata, pro hac vice, par parenthese, parenthetically, by way of parenthesis, incidentally, while speaking of, while on the subject, extempore, on the spur of the moment, on the spur of the occasion, on the spot, carpe diem occasionem cognosce, one's hour is come, the time is up, that reminds me, now that you mention it, come to think of it, bien perdu bien connu, e sempre l'ora, ex quovis ligno non fit Mercurius, nosce tempus, nunc aut nunquam.