Meaning

verb express gratitude or show appreciation to

originFrom Middle English thank (“gratitude; expression of gratitude, thanks; attractiveness; commendation, praise; God’s grace; goodwill; merit, reward; mind, thought”), from Old English þanc, þonc (“gratitude; expression of gratitude, thanks; favour, grace; mind, thought; pleasure, satisfaction”), from Proto-Germanic *þankaz (“gratitude; expression of gratitude, thanks; mind, thought; remembrance”),…

Etymology from Wiktionary, CC BY-SA 3.0