I`sor·rop'ic adjective [ Greek 'iso`rropos in equipoise; 'i`sos equal + 'roph` downward inclination or momentum.] Of equal value. Isorropic line (in a diagram) (Geom.) , the locus of all the points for which a specified function has a constant value... Found on http://www.encyclo.co.uk/webster/I/103