The Collaborative International Dictionary
Why-not
Why-not \Why"-not`\, n. A violent and peremptory procedure without any assigned reason; a sudden conclusive happening. [Obs.]
When the church
Was taken with a why-not in the lurch.
--Hudibras.
This game . . . was like to have been lost with a
why-not.
--Nug[ae]
Antiq.
Wiktionary
why-not
n. (context obsolete English) A violent and peremptory procedure without any assigned reason; a sudden conclusive happening.