i‧on‧o‧sphere /aɪˈɒnəsfɪə $ aɪˈɑːnəsfɪr/
noun[
Date: 1900-2000;
Origin: ion + -sphere (as in atmosphere)]
the ionosphere the part of the
atmosphere which is used to help send radio waves around the Earth
[TahlilGaran] Dictionary of Contemporary English ▲