Definify.com

Webster 1913 Edition

Noun.

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

Nugae Antiq.

See also: why not

(obsolete) A violent and peremptory procedure without any assigned reason; a sudden conclusive happening.

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 — Harington.