eu·tec·tic 
(y-tĕktĭk)
(y-tĕktĭk)adj.
1. Of, relating to, or formed at the lowest possible temperature of solidification for any mixture of specified constituents. Used especially of an alloy whose melting point is lower than that of any other alloy composed of the same constituents in different proportions.
2. Exhibiting the constitution or properties of such a solid.
n.
1. A eutectic mixture, solution, or alloy.
2. The eutectic temperature.
[From Greek eutēktos, easily melted : eu-, eu- + tēktos, melted (from tēkein, to melt).]