Solemn.

Solemn \Sol"emn\, a. [OE. solempne, OF. solempne, L. solemnis,
   solennis, sollemnis, sollennis; sollus all, entire + annus a
   year; properly, that takes place every year; -- used
   especially of religious solemnities. Cf. {Silly}, {Annual}.]
   1. Marked with religious rites and pomps; enjoined by, or
      connected with, religion; sacred.
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            His holy rites and solemn feasts profaned. --Milton.
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            The worship of this image was advanced, and a solemn
            supplication observed everry year.    --Bp.
                                                  Stillingfleet.
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   2. Pertaining to a festival; festive; festal. [Obs.] "On this
      solemn day." --Chaucer.
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   3. Stately; ceremonious; grand. [Archaic]
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            His feast so solemn and so rich.      --Chaucer.
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            To-night we hold a splemn supper.     --Shak.
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   4. Fitted to awaken or express serious reflections; marked by
      seriousness; serious; grave; devout; as, a solemn promise;
      solemn earnestness.
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            Nor wanting power to mitigate and swage
            With solemn touches troubled thoughts. --Milton.
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            There reigned a solemn silence over all. --Spenser.
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   5. Real; earnest; downright. [Obs. & R.]
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            Frederick, the emperor, . . . has spared no expense
            in strengthening this city; since which time we find
            no solemn taking it by the Turks.     --Fuller.
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   6. Affectedly grave or serious; as, to put on a solemn face.
      "A solemn coxcomb." --Swift.
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   7. (Law) Made in form; ceremonious; as, solemn war;
      conforming with all legal requirements; as, probate in
      solemn form. --Burrill. --Jarman. --Greenleaf.
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   {Solemn League and Covenant}. See {Covenant}, 2.
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   Syn: Grave; formal; ritual; ceremonial; sober; serious;
        reverential; devotional; devout. See {Grave}.
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213 Moby Thesaurus words for "solemn":
      Christian, Christianlike, Christianly, admiring, adorant, adoring,
      apotheosizing, arid, aristocratic, august, awe-inspiring, awed,
      awesome, awestricken, awestruck, barren, believing, black, blah,
      blank, bleak, bloated, bloodless, bombastic, celebrating,
      celebrative, ceremonial, ceremonious, characterless, cold,
      colorless, commemorating, commemorative, conventional, courtly,
      cultish, cultist, cultistic, dark, dead, decorous, deifying,
      demure, devoted, devotional, devout, dignified, dismal, divine,
      draggy, drear, drearisome, dreary, dry, dryasdust, dull, dusty,
      dutiful, earnest, ecclesiastical, effete, elephantine, elevated,
      empty, etiolated, fade, faithful, fatal, fateful, flat, flatulent,
      formal, formidable, frowning, full, funebrial, funereal, gassy,
      gloomy, glum, grand, grandiloquent, grave, gray, grim, grim-faced,
      grim-visaged, hallowed, heavy, hero-worshiping, hieratic, ho-hum,
      hollow, holy, idolatrous, idolizing, imploring, important,
      imposing, impressive, in awe, in the dust, inane, inexcitable,
      inflated, insipid, inspiring, jejune, kingly, leaden, lifeless,
      liturgic, liturgical, lofty, long-faced, lordly, low-spirited,
      magisterial, magnificent, majestic, memorial, mirthless, moderate,
      momentous, morbid, morose, moving, no-nonsense, noble,
      on bended knee, ostentatious, overwhelming, pale, pallid,
      pedestrian, pietistic, pious, plenary, plodding, pointless, poky,
      pompous, ponderous, pontifical, portentous, prayerful, precative,
      precatory, princely, prostrate before, queenly, regal, religious,
      reserved, reverent, reverential, ritual, ritualistic, royal,
      sacerdotal, sacramental, sacred, saturnine, sedate, self-important,
      serious, slow, sober, sober-minded, sobersided, somber, sombrous,
      spiritless, staid, stately, statuesque, sterile, stiff, stilted,
      stodgy, stone-faced, straight-faced, stuffy, sublime, superficial,
      suppliant, supplicant, supplicatory, swollen, taciturn, tasteless,
      tedious, temperate, theistic, thoughtful, triste, tumid, turgid,
      unlively, unsmiling, vapid, venerable, venerational, venerative,
      weariful, wearisome, weary, weighty, well-mannered, wooden,
      worshipful, worshiping, worthy