Definition of "flexible"

adjective:
- Capable of being flexed or bent without breaking; able to be turned, bowed, or twisted, without breaking; pliable; not stiff or brittle.
  
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- Willing or ready to yield to the influence of others; not invincibly rigid or obstinate; tractable; manageable; ductile; easy and compliant; wavering.
  
  from Wiktionary, Creative Commons Attribution/Share-Alike License
- Capable or being adapted or molded; plastic,; as, a flexible language.
  
  from Wiktionary, Creative Commons Attribution/Share-Alike License
noun:
- Something that is flexible.
  
  from Wiktionary, Creative Commons Attribution/Share-Alike License