In a way that cannot be varied, or changed.(adverb)
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Use "unchangeably" in a sentence
"To undermine the concept of what is ‘natural’ and unchangeably right, and to argue that we have change morality and nature as we please, is to undermine the premises on which liberal society itself is built."
"The Chicago church where President Obama belonged for 20 years, Trinity United Church of Christ, is theologically liberal, eschewing scriptural inerrancy and taking apostolic creeds as "testimonies" of faith, rather than literally, unchangeably true."
"I have a few friends from Sri Lanka, and it always disheartens me to listen to them talk about the situation being unchangeably bad there."