ETYMOLOGY
from Latin fallax: from fallere (to deceive) + -ity
EXAMPLE
“...saying that then it shall appear before his Counsell the great deceit fallaxity and crafty waies cast and invironed to destroy and holy to an nyntyssement of your honor for ever…”
From: The Berkeley Manuscripts
The Lives of the Berkeleys
Lords of the Honour, Castle and Manor of Berkeley
In the County of Gloucester, From 1066 to 1618
John Smyth, a1641
Lexicophilia 