What is the meaning of functional?

adjective

• Designed for or capable of a particular function or use.
  • usage: "a style of writing in which every word is functional"; "functional architecture"
• Involving or affecting function rather than physiology.
  • usage: "functional deafness"
• Relating to or based on function especially as opposed to structure.
  • usage: "the problem now is not a constitutional one; it is a functional one"; "delegates elected on a functional rather than a geographical basis"
• Fit or ready for use or service.
  • usage: "the toaster was still functional even after being dropped"; "the lawnmower is a bit rusty but still usable"; "an operational aircraft"; "the dishwasher is now in working order"
  • synonyms: usable, useable, operable, operational
• Designed for or adapted to a function or use.
  • usage: "functional education selects knowledge that is concrete and usable rather than abstract and theoretical"; "functional architecture"
• Of e. G. A machine. ( performing or capable of performing)
  • usage: "in running (or working) order"; "a functional set of brakes"
  • synonyms: running, operative, working