Definition of "Through" :

adjective: (of a route or journey etc.) continuing without requiring stops or changes

"A through street."

adjective: having finished or arrived at completion

"After the treatment, the patient is through except for follow-up."

adverb: throughout the entire extent

"Got soaked through in the rain."

adverb: over the whole distance

"This bus goes through to New York."

adverb: in diameter

"This cylinder measures 15 inches through."

adverb: from beginning to end

"Read this book through."

adverb: to completion

"Think this through very carefully!."