The Collaborative International Dictionary of English v.0.48:

Solemnize \Sol"em*nize\, v. t. [imp. & p. p. Solemnized; p.
   pr. & vb. n. Solemnizing.] [Cf. F. solemniser,
   sollemniser.]
   1. To perform with solemn or ritual ceremonies, or according
      to legal forms.
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            Baptism to be administered in one place, and
            marriage solemnized in another.       --Hooker.
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   2. To dignify or honor by ceremonies; to celebrate.
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            Their choice nobility and flowers . . .
            Met from all parts to solemnize this feast.
                                                  --Milton.
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   3. To make grave, serious, and reverential.
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            Wordsworth was solemnizzed and elevated by this his
            first look on Yarrow.                 --J. C.
                                                  Shairp.
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            Every Israelite . . . arose, solemnized his face,
            looked towards Jerusalem . . . and prayed. --L.
                                                  Wallace.
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