mog, n.¹ — Green’s Dictionary of Slang

mog n.¹

also mogue

[? Fr. se moquer de, to jeer, to deride]

a lie; thus no mogue, no lie.

1835		G. Kent Modern Flash Dict.
1848		Flash Dict. in Sinks of London Laid Open.
2023		R. Milward Man-Eating Typewriter 13: mogues! mogues! mogues!* [f.n.] * ‘lies! lies! lies!’.