Useful words that sadly have no English equivilent

Schadenfreude (German): pleasure in someone else's misfortune

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Espirit d'escalier (French): When you think of the perfect verbal comeback... much too late

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Mamihlapinatapai (Yaghan): look shared by two people with each wishing that the other will initiate something that both desire but which neither one wants to start

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backpfeifengesicht (German): A face badly in need of a fist

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Nunchi (Korean): The art of not becoming a Backpfeifengesicht

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shlimazl (Yiddish): Somebody who has nothing but [very] bad luck

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honne and tatemae (Japan): The first is reality as you understand it, the second is reality as filtered through what society expects

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Tingo (Pascuense): To borrow from a friend until he has nothing left

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Sgiomlaireachd (Scottish Gaelic): When people interrupt you at meal time

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Desenrascanco (Portuguese): slapping together a solution to a problem at the last minute, with no advanced planning, and no resources