Whit, Whitsun, WhitSunday, Pentecost - pente=five - the 7th Sunday after Easter or the 50th day and Whit, a typically English shortening of White (Sunday)....the appearance of the Holy Ghost and ghosts are, of course, white (or are they?).
Anyway today is Whitsun or Pentecost Sunday - something I never really got into - probably owing to the speaking in tongues business enjoyed by the disciples And they were all filled with the Holy Ghost, and began to speak with other tongues, as the Spirit gave them utterance - Acts 2:1-6 and being Lutheran, Episcopal and Methodist in my life, well, if I need people speaking in tongues I'll dial up a politician or watch Faux Noise.....but if you write a calm and fitting composition like John Adams did, well I'm "all in".