Whitsun

[hwit-suh n, wit-] /ˈʰwɪt sən, ˈwɪt-/
adjective
1.
of or pertaining to Whitsunday or Whitsuntide.
noun
2.
Whitsunday or Whitsuntide.
Origin
1250-1300; Middle English Whitsone(n), shortening of whitsonenday (by analysis as whitsonen-day); see Whitsunday
British Dictionary definitions for Whitsun

Whitsun

/ˈwɪtsən/
noun
1.
short for Whitsuntide
adjective
2.
of or relating to Whit Sunday or Whitsuntide
Word Origin and History for Whitsun

late 13c., contraction of Whitsunday.