secondary_school has definitions from the field of education
1
[ noun ] (education) a school for students intermediate between elementary school and college; usually grades 9 to 12

Used in print

(Edward E. Kelly, S.J., "Christian Unity in England"...)

Almost daily something is reported which feeds this Catholic hope in England : statistics of the increasing numbers of converts and Irish Catholic immigrants ; news of a Protestant minister in Leamington who has offered to allow a Catholic priest to preach from his pulpit ; a report that a Catholic nun had been requested to teach in a non-Catholic secondary_school during the sickness of one of its masters ; the startling statement in a respectable periodical that `` Catholics , if the present system is still in_operation , will constitute almost one-third of the House_of_Lords in the next generation '' ; a report that 200 Protestant clergymen and laity attended a votive Mass offered for Christian unity at a Catholic_church in Slough during the Church Unity Octave .

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