In a blamable manner; in a manner deserving blame(adverb)
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Use "blamably" in a sentence
"Knight, somewhat blamably, keenly enjoyed sparring with the palpitating mobile creature, whose excitable nature made any such thing a species of cruelty."
"In the good old times they were as scrupulously exact in these matters, as they are now most blamably lax."
"Lee, by the way, had constantly insinuated that Franklin was blamably lax, if not actually untrustworthy, in money matters, though all the while he and his friend Izard had been quite shameless in extorting from the doctor very large sums for their own expenses."