Definitions
1.nounA group of three.
2.nounOne of a group of three.
3.nounOne of a group of three siblings born at the same time to the same mother.
4.nounA group of three notes played or written where two notes would ordinarily be; a form of tuplet.
5.nounA triquark.
6.nounA quantum state with three allowed projections for the spin.
7.nounA constructed gem consisting of a thin slice of natural opal sandwiched between a clear glass or quartz top and a synthetic or stone backing that enhances the colour of the opal.