Synonyms for Thanksgiving (same or very similar meaning)
WordNet sense 1 (fourth Thursday in November in the United States; second Monday in October in Canada; commemorates a feast held in 1621 by the Pilgrims and the Wampanoag):
Thanksgiving Day
WordNet sense 2 (a short prayer of thanks before a meal):
blessing, grace
From the ODE community, based on WordNet
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