Correspondence school and University extension

Correspondence school noun - A school that teaches nonresident students by mail.

University extension and correspondence school are semantically related. In some cases you can replace phrase "University extension" with "Correspondence school", this phrases are similar.

University extension noun - An educational opportunity provided by colleges and universities to people who are not enrolled as regular students.

Correspondence school and university extension are semantically related. Sometimes you can replace phrase "Correspondence school" with "University extension", this phrases are similar.