詐偽 is read as さぎ (sagi) and means lie.
さぎ
sagi
saying you're going to do something but in the end not doing it
さしょう
misrepresentation
さしゅ
defrauding
さぎし
swindler
さじゅつ
swindling
さがい
fraud
さびょう
feigned illness
こぎ
fallacy
しんぎ
truth or falsehood
にせ
pseudo-
ぎぶつ
spurious article
ぎぞう
forgery