Examples
“For instance, there is the doctor, whom Mrs.P. does not condescend to visit: that man educates a mirific family, and is loved by the poor for miles round: and gives them port-wine for physic and medicine, gratis.”
“I vow and swear by the handle of my paper lantern that it was a gallant, a mirific, nay, a most admirable piece.”
Five books of the lives, heroic deeds and sayings of Gargantua and his son Pantagruel
“Place de la Bourse, and having had to listen to another of such mirific demonstrations about a scheme from which both were to derive millions, answered drily:”
“He, too, is a dictator, at once humorous and tragic like the mirific doctor, but, unlike him, infinitely subtle.”
“What are they that they should interfere with the great mirific and most assuaging and comfortable feast of wit to which I am now about to introduce you!”
“It was the same Henry Monnier who, meeting him another time on the Place de la Bourse, and having had to listen to another of such mirific demonstrations about a scheme from which both were to derive millions, answered drily:”
Balzac
“It was evident that the family, after the arrival of the mirific Jim Deming, had grown somewhat accustomed to”
“Being a loyal little soul, the child retained his affection for Auntie Anne, but he was swept off his little feet by his mirific parent.”
“His pretty French wife, who knows no English, charmingly dishevelled, uncorseted, free, in a dubious _peignoir_ trimmed with artificial lace -- she who moulded in mirific tights, sea-green with reflections of mother-of-pearl, like Venus Anadyomene, does the tight rope act every afternoon and evening -- sits a little way apart, busy with needle and thread repairing a sorry handful of garments which to-night will be tense with some portion of her shapely body.”
“I don't know how his consciousness could have arrived at appreciation of Antoinette's cooking, for he talked all through dinner, giving me an account of his mirific adventures in foreign cities.”
Lists
‘mirific’ hasn't been added to any lists yet.

pavonine (adj): the more elegant and economical form of the term mirifical meaning "working wonders", "wonderful".
This word may be one of the uncommon monovocalic trisyllables in the English language.
about 1 year ago mollusque said:
A mirific word! I have fond memories of playing it in a game of Scrabble. My opponent didn't challenge but the word was not in OSPD1, the then current dictionary of record. It is in MW3 and OED2.
about 1 year ago Verbophile said: edit
Working wonders;wonderful Jul 16, 2009
hernesheir (adj): the more elegant and economical form of the term mirifical meaning "working wonders", "wonderful".
This word may be one of the uncommon monovocalic trisyllables in the English language. Jan 7, 2009
mollusque A mirific word! I have fond memories of playing it in a game of Scrabble. My opponent didn't challenge but the word was not in OSPD1, the then current dictionary of record. It is in MW3 and OED2. Nov 5, 2007
pavonine Working wonders;wonderful Nov 5, 2007