sap·phire 
(săfīr′)
(săfīr′)n.
1. A clear hard variety of corundum used as a gemstone that is usually blue but may be any color except red.
2. A corundum gem.
3. The blue color of a gem sapphire.
adj.
1. Made of or resembling a gem sapphire.
2. Having the color of a blue sapphire.
3. Of or relating to a 65th anniversary.
[Middle English saphir, from Old French safir, from Latin sapphīrus, from Greek sappheiros, of Semitic origin; akin to Hebrew sappîr, a precious stone.]