The Collaborative International Dictionary of English v.0.48:

School \School\, n. [OE. scole, AS. sc?lu, L. schola, Gr. ?
   leisure, that in which leisure is employed, disputation,
   lecture, a school, probably from the same root as ?, the
   original sense being perhaps, a stopping, a resting. See
   Scheme.]
   1. A place for learned intercourse and instruction; an
      institution for learning; an educational establishment; a
      place for acquiring knowledge and mental training; as, the
      school of the prophets.
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            Disputing daily in the school of one Tyrannus.
                                                  --Acts xix. 9.
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   2. A place of primary instruction; an establishment for the
      instruction of children; as, a primary school; a common
      school; a grammar school.
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            As he sat in the school at his primer. --Chaucer.
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   3. A session of an institution of instruction.
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            How now, Sir Hugh! No school to-day?  --Shak.
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   4. One of the seminaries for teaching logic, metaphysics, and
      theology, which were formed in the Middle Ages, and which
      were characterized by academical disputations and
      subtilties of reasoning.
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            At Cambridge the philosophy of Descartes was still
            dominant in the schools.              --Macaulay.
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   5. The room or hall in English universities where the
      examinations for degrees and honors are held.
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   6. An assemblage of scholars; those who attend upon
      instruction in a school of any kind; a body of pupils.
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            What is the great community of Christians, but one
            of the innumerable schools in the vast plan which
            God has instituted for the education of various
            intelligences?                        --Buckminster.
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   7. The disciples or followers of a teacher; those who hold a
      common doctrine, or accept the same teachings; a sect or
      denomination in philosophy, theology, science, medicine,
      politics, etc.
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            Let no man be less confident in his faith . . . by
            reason of any difference in the several schools of
            Christians.                           --Jer. Taylor.
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   8. The canons, precepts, or body of opinion or practice,
      sanctioned by the authority of a particular class or age;
      as, he was a gentleman of the old school.
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            His face pale but striking, though not handsome
            after the schools.                    --A. S. Hardy.
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   9. Figuratively, any means of knowledge or discipline; as,
      the school of experience.
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   Boarding school, Common school, District school,
   Normal school, etc. See under Boarding, Common,
      District, etc.

   High school, a free public school nearest the rank of a
      college. [U. S.]

   School board, a corporation established by law in every
      borough or parish in England, and elected by the burgesses
      or ratepayers, with the duty of providing public school
      accommodation for all children in their district.

   School committee, School board, an elected committee of
      citizens having charge and care of the public schools in
      any district, town, or city, and responsible for control
      of the money appropriated for school purposes. [U. S.]

   School days, the period in which youth are sent to school.


   School district, a division of a town or city for
      establishing and conducting schools. [U.S.]

   Sunday school, or Sabbath school, a school held on Sunday
      for study of the Bible and for religious instruction; the
      pupils, or the teachers and pupils, of such a school,
      collectively.
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The Collaborative International Dictionary of English v.0.48:

Boarding \Board"ing\, n.
   1. (Naut.) The act of entering a ship, whether with a hostile
      or a friendly purpose.
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            Both slain at one time, as they attempted the
            boarding of a frigate.                --Sir F.
                                                  Drake.
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   2. The act of covering with boards; also, boards,
      collectively; or a covering made of boards.
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   3. The act of supplying, or the state of being supplied, with
      regular or specified meals, or with meals and lodgings,
      for pay.
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   Boarding house, a house in which boarders are kept.

   Boarding nettings (Naut.), a strong network of cords or
      ropes erected at the side of a ship to prevent an enemy
      from boarding it.

   Boarding pike (Naut.), a pike used by sailors in boarding a
      vessel, or in repelling an attempt to board it. --Totten.

   Boarding school, a school in which pupils receive board and
      lodging as well as instruction.
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WordNet (r) 3.0 (2006):

boarding school
    n 1: a private school where students are lodged and fed as well
         as taught [ant: day school]