Refers specifically to the American Thanksgiving holiday. Not used for general harvest festivals.
There is a custom of eating turkey on Thanksgiving.
customer appreciation event; thank-you sale
Used by businesses for sales campaigns or events thanking customers for their patronage. Not a literal translation of Thanksgiving.
I bought a lucky bag at the department store's customer appreciation sale.
great customer appreciation sale
Compound of 感謝 (kansha, 'thanks, gratitude') and 祭 (sai, 'festival'). The sense 'Thanksgiving' is a direct translation of the English term; the commercial sense is a Japanese extension.