What is the meaning of through?

adjective

• Having finished or arrived at completion.
  • usage: "certain to make history before he's done"; "it's a done deed"; "after the treatment, the patient is through except for follow-up"; "almost through with his studies"
  • synonyms: done, through with
• Of a route or journey etc.. ( continuing without requiring stops or changes)
  • usage: "a through street"; "a through bus"; "through traffic"

adverb

• From beginning to end.
  • usage: "read this book through"
• Over the whole distance.
  • usage: "this bus goes through to New York"
• To completion.
  • usage: "think this through very carefully"
• In diameter.
  • usage: "this cylinder measures 15 inches through"
• Throughout the entire extent.
  • usage: "got soaked through in the rain"; "I'm frozen through"; "a letter shot through with the writer's personality"; "knew him through and through"; "boards rotten through and through"
  • synonyms: through and through