A philosopher or other thinker who advocates or employs a deontological approach to ethics.(noun)
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Use "deontologist" in a sentence
"And one needn't be a raving deontologist to recognize that deontology isn't merely solipsistic."
"Being a deontologist does not protect you from criticism."
"A deontologist who thinks that child molestation, rape, and murder should all be perfectly legal but who thinks that putting your shoes on between the hours of 12 AM and 5 PM should be punished by the death penalty is still as subject to criticism as anyone else."