A euphemism for gay
From the last line of the poem "Monday's Child":
"The child born on the Sabbath day is bonnie and blithe and good and gay"
"I wouldn't ask him out if I were you... I hear he was 'born on a sunday'"
by Cecilll November 5, 2017
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Gay, a secret way of saying someone's gay

Taken from the last line that one old poem "Monday's Child is Fair of Face"
"A child born on the Sabbath day is bonnie and blithe and good and gay"
Jennifer: Craig's kinda cute, dontchya think?
Dani: Yeah but he's...yknow... born on a Sunday
Jennifer: Oohhh nevermind then
by Cecilll August 8, 2017
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