The term ‘endeavor’ is used as both a noun and a verb.
As a noun, the term refers to refer to an enterprise or venture that is undertaken. It can mean any strenuous effort or attempt at success. For example: I am undertaking a business endeavor. Here the speaker is trying to undertake an attempt to succeed at business, whatever that may be.
As a verb, the term ‘endeavor’ is used to refer to attempt or try do something. For example: He endeavors to make this party a success. Here, he is trying to ensure that the party is a success.
Endeavor can also be used to refer to exert oneself to do or affect something. Also to make an effort or to strive for something. For example: We must constantly endeavor if we are to succeed. Here, the speaker is telling us to work hard to succeed in what we want.
The word ‘endeavor’ comes from Middle English endeveren, which means “to make an effort.” The term is rooted in Middle French ‘en devoir’ which means “(to make it) one’s duty (to do)”, as ‘devoir’ in French means ‘duty.’