The term "flex" has multiple meanings depending on its context.
1) In a general sense, flex can refer to being able to bend or adjust easily without breaking. For example, "This material is very flexible."
2) Flex can also be used as an abbreviation for "flexible," which means capable of being bent or shaped without breaking. An example usage would be: "She's a very flexible dancer."
3) In the world of technology and computing, flex refers to a programming language that allows developers to create mobile applications using a single codebase that can work across multiple platforms.
4) Lastly, in slang terms, flex can mean showing off or bragging about something, usually in reference to one's possessions or achievements. An example usage would be: "He was just trying to flex by talking about how much money he makes."