Raison d'être is a French phrase meaning 'reason for being'. It is used to describe the purpose or justification for something's existence. The two crossword solutions, 'être' and 'etat', are both French words that can be used to explain the concept of raison d'être. 'Être' is the infinitive form of the verb 'to be' and is used to describe the state of being or existence of something. 'État' is a noun that refers to a nation or political entity, and is often used to refer to the government or governing body of a country. Together, these two words can be used to explain the concept of raison d'être, which is the purpose or justification for something's existence.