[ahy-suh-jee-uh-thurm] /ˌaɪ səˈdʒi əˌθɜrm/
an imaginary line connecting all points within the earth having the same mean temperature.
an imaginary line below the surface of the earth connecting points of equal temperature
[ahy-suh-glos, -glaws] /ˈaɪ səˌglɒs, -ˌglɔs/ noun 1. (in the study of the geographical distribution of dialects) a line on a map marking the limits of an area within which a feature of speech occurs, as the use of a particular word or pronunciation. /ˈaɪsəʊˌɡlɒs/ noun 1. a line drawn on a map around the area […]
[ahy-suh-gon] /ˈaɪ səˌgɒn/ noun 1. a polygon having all angles equal. /ˈaɪsəʊˌɡɒn/ noun 1. an equiangular polygon
[ahy-sog-uh-nl] /aɪˈsɒg ə nl/ adjective 1. equiangular; isogonic. noun 2. .
noun 1. an imaginary line, or one drawn on a map, connecting all points of equal magnetic declination.