from Latin mendāciloquus (from mendāci-, -mendax mendacious + loqui to speak) + -ent
1656 - Glossographia, Thomas Blount - Mendaciloquent, that tells lies
From: The Book of the Bastiles:
Or, The History of the Working of the New Poor-Law
By G.R. Wythen Baxter, 1841
Part I. Letters, Sketches, Petitions, Addresses, Etc.
Mr. Richard Oastler, the People's Patriot