Available Definitions:
1) n. - Native alumina or aluminium sesquioxide, Al2O3; corundum; esp., the blue transparent variety of corundum, highly prized as a gem.
2) n. - The color of the gem; bright blue.
3) n. - Any humming bird of the genus Hylocharis, native of South America. The throat and breast are usually bright blue.
4) a. - Of or resembling sapphire; sapphirine; blue.