overturn vs overthrow

overturn and overthrow both are nouns.

Word	Noun	Adjective	Verb	Adverb
overturn	Yes	No	Yes	No
overthrow	Yes	No	Yes	No

As verbs, overturn and overthrow are synonyms defined as:

Other synonyms of overturn include override, overrule, reverse.

As verbs, overturn and overthrow are synonyms defined as:

Other synonyms of overturn include bring down, subvert.

overturn (noun)	overthrow (noun)
the act of upsetting something	the termination of a ruler or institution (especially by force)
an improbable and unexpected victory	the act of disturbing the mind or body

overturn (verb)	overthrow (verb)
change radically	rule against
rule against	cause the downfall of; of rulers
cancel officially
turn from an upright or normal position
cause to overturn from an upright or normal position
cause the downfall of; of rulers