"High school" is the universally-accepted term in the US, and means four years before university. "Junior" high school is not a universal term, though exists i

"High school" is the universally-accepted term in the US, and means four years before university. "Junior" high school is not a universal term, though exists in some areas. "Senior high school" is a term I've never heard before, appears uncited on that wikipedia page, and were I to say it to anyone I know they would look at me funny.