Oratorio: my music dictionary defines it as a large-scale work on a religious subject, usually performed in a concert hall.
The name has its roots in the smaller versions on the theme originally intended to be heard in the oratories of 17th century Rome.
Of course, the most famous of oratorios is the one most associated with Christmas, but in fact first performed in Dublin just after Easter in 1742 - Handel's Messiah.
George Frideric Handel was born only a matter of weeks before Johann Sebastian Bach in 1685, in the same region of eastern Germany.
Where Bach spent the greater part of his life at home, becoming synonymous with Leipzig where he was director of music for more than a quarter of a century, Handel followed his star.
Though his first steps were in the arena of church music, a seat in the orchestra pit at the Hamburg Opera convinced him this was his calling.
He moved to Italy, opera's home turf. His first opera there, Rodrigo, premiered in Florence in 1707.
His final Italian opera - Agrippina - was first staged in Venice at Christmas 1709, opening the carnival season. It ran for 27 consecutive nights - something unheard of then - and confirmed his growing reputation.
Buoyed by success, he returned to Germany, where he took charge of the music for the Electress Sophia of Hanover, heir to the British throne. Her son would become King George I.
The connection with England was made. Handel paid a visit, and scored a huge success with Rinaldo, the first "Italian" opera specifically written for the London stage. The composer-cum-impresario saw a business opportunity. There was nobody else doing this.
With the promise of a salary of £200 from the then Queen Anne (around €50,000 in today's money, so hardly a vast fortune), he quit Hanover and based himself in Britain.
He proved to be a shrewd investor, well ahead of the pack. And it wasn't just the music that proved a winner.
His productions would feature special effects. One of them had dragons breathing fire, and a flock of birds as part of the cast.
In all, Handel would write 38 operas for the London stage. As well, there were royal commissions.
'Zadok the Priest' - best known now in its reworking as the theme music for television coverage of football's Champions League - is an anthem composed for the coronation of King George II of Britain in 1727.
But whenever an operation becomes successful, competition cannot be far behind. In modern parlance, trading conditions became more difficult.
On top of that, in the way that fashions change, Italian opera was losing its appeal. An invitation from Dublin came at just the right time.
The city boasted one of the few concert halls in Britain or Ireland, a venue in Fishamble Street behind Christ Church Cathedral.
Neale's Music Hall would become famous the world over after events in the spring of 1742.
There, Handel put on a series of subscription concerts, which proved extremely popular. This would be just the place to put on his latest work.
This was "something special" he'd been asked to compose to raise funds for Mercer's Hospital.
So, at noon on Tuesday, April 13 that year, Handel's Messiah took flight. And the rest, as they say, is history.
George Hamilton presents 'The Hamilton Scores' on RTÉ lyric fm from 10am each Saturday and Sunday