verb
To recognize an occasion
To honor
To indulge in celebration
celebrate means to mark an occasion or event, esp. a joyous one, with ceremonies or festivities let's celebrate your promotion; to commemorate is to honor the memory of some person or event, as with a ceremony or memorialto commemorate Lincoln's birthday; to solemnize is to use a formal, serious ritual to observe an occasionto solemnize a marriage; observe and keep mean to respectfully mark a day or occasion in the prescribed and appropriate manner to observe, or keep, a religious holiday
See celebrate in Webster's New World Roget's A-Z Thesaurus II
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