Namesakes
Fictional Characters from Television:
1 character
Misty Day 2011 American Horror Story 
Hall-of-Famers:
1 baseball, 1 ice hockey
(ice hockey) Clarence "Hap" Day 1961
(baseball) Leon Day 1995
Notable Actors and Actresses:
2 actors, 1 actress
Doris Day 1922-2019
Daniel Day-Lewis 1957-
Simon Paisley Day 1967-
Notable Athletes:
1 baseball, 1 football, 1 ice hockey, 1 rugby
(ice hockey) Clarence "Hap" Day 1901-1990
(baseball) Leon Day 1916-1995
(rugby) Dominic Day 1985-
(football) Dillon Day 1991-
Notable Musicians:
1 singer
Doris Day 1922-2019
Olympic Medalists:
1 bronze
(bronze) Christine Day 2012 4x400 m relay
Oscar Award Winners:
1 actor
(actor) Daniel Day-Lewis 1989; 2007; 2012 My Left Foot; There Will Be Blood; Lincoln