/trin"i tee/ , n. , pl. Trinities for 2, 4.
1. Also called Blessed Trinity, Holy Trinity . the union of three persons (Father, Son, and Holy Ghost) in one Godhead, or the threefold personality of the one Divine Being.
2. a representation of this in art.
3. See Trinity Sunday .
4. ( l.c. ) a group of three; triad.
5. ( l.c. ) the state of being threefold or triple.
[ 1175-1225; ME Trinite trinitas triad, trio, the Trinity, equiv. to trin ( us ) threefold (see TRINE) + -itas -ITY ]