Webster's Revised Unabridged Dictionary · 1913

Falsely

Falsely , adverb

In a false manner; erroneously; not truly; perfidiously or treacherously.
O falsely, falsely murdered. — Shakespeare
Oppositions of science, falsely so called. — 1 Tim. vi. 20
Will ye steal, murder... and swear falsely? — Jer. vii. 9