In an illicit manner; illegally, immorally or inappropriately.(adverb)
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Use "illicitly" in a sentence
"Clenbuterol was banned by the European Union in 1996 but it is still administered illicitly by some cattle farmers."
"One in four GIs admit to illicitly using narcotic medication during a 12-month period, according to a 2008 Pentagon health survey."
"Going after his plane usage is silly and they have wasted more money on their "investigation" than total amount spent on the handful of hours they claim were illicitly used."