As nouns the difference between apostacy and ecumenism
is that apostacy is abandonment of religion (see apostasy) while ecumenism is (philosophy) ecumenical doctrines and practices, especially as manifested in the ecumenical movement.
apostacy
Noun
(apostacies)
Abandonment of religion (see apostasy)
(legal) the ancient criminal offence of heresy or non-belief in religion.
ecumenism
English
Alternative forms
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Noun
(
en noun)
(philosophy) Ecumenical doctrines and practices, especially as manifested in the ecumenical movement.
References
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