apostasy vs tergiversation

apostasy and tergiversation both are nouns.

Word	Noun	Adjective	Verb	Adverb
apostasy	Yes	No	No	No
tergiversation	Yes	No	No	No

As nouns, apostasy and tergiversation are synonyms defined as:

apostasy (noun)	tergiversation (noun)
the act of abandoning a party for cause	falsification by means of vague or ambiguous language
the state of having rejected your religious beliefs for your political party or a cause (often in favor of opposing beliefs or causes)	the act of abandoning a party for cause