c. 1200, "with intent to deceive, deceitfully," from false + -ly (2). From c. 1300 as "wrongly; untruthfully;" early 14c. as "incorrectly."
a seduction on my part would land us with the necessity to rise, bathe and dress, chat falsely about this and that, and emerge into the rest of the evening as though nothing had happened
to credit Lister with the first formulation of the basic principle of stratigraphy would be to bestow credit falsely