highschool

from WordNet (r) 3.0 (2006)

highschool
    n 1: a public secondary school usually including grades 9
         through 12; "he goes to the neighborhood highschool" [syn:
         {senior high school}, {senior high}, {high}, {highschool},
         {high school}]

from The Collaborative International Dictionary of English v.0.48

highschool \highschool\, high school \high school\n.
   a public secondary school usually including grades 9 through
   12; as, he goes to the neighborhood highschool.

   Syn: senior high school, senior high, high, high school.
        [WordNet 1.5]