In an unrelenting manner; rigidly; cruelly.(adverb)
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Use "unrelentingly" in a sentence
"Indeed, Robotron: 2084 is still considered to be a high-water mark in unrelentingly difficult shooters."
"The first portrayed Kerry in unrelentingly negative terms, permanently damaging him, while the second produced dramatic innovations in direct mail and voter technology, enabling Bush to identify and target potential voters with pinpoint precision."
"Mr de Klerk was "unrelentingly" interfering with the public disclosure of this."