What is the meaning of flex?

noun

• The act of flexing.
  • usage: "he gave his biceps a flex to impress the ladies"

verb

• Contract.
  • usage: "flex a muscle"
• Exhibit the strength of.
  • usage: "The victorious army flexes its invincibility"
• Form a curve.
  • usage: "The stick does not bend"
  • synonyms: bend
• Bend a joint.
  • usage: "flex your wrists"; "bend your knees"
  • synonyms: bend
• Cause (a plastic object) to assume a crooked or angular form.
  • usage: "bend the rod"; "twist the dough into a braid"; "the strong man could turn an iron bar"
  • synonyms: bend, deform, twist, turn