feloniously

from The Collaborative International Dictionary of English v.0.48

Felonious \Fe*lo"ni*ous\, a.
   Having the quality of felony; malignant; malicious;
   villainous; traitorous; perfidious; in a legal sense, done
   with intent to commit a crime; as, felonious homicide.
   [1913 Webster]

         O thievish Night,
         Why should'st thou, but for some felonious end,
         In thy dark lantern thus close up the stars? --Milton.
   -- {Fe*lo"ni*ous*ly}, adv. -- {Fe*lo"ni*ous*ness}, n.
   [1913 Webster]

from Bouvier's Law Dictionary, Revised 6th Ed (1856)

FELONIOUSLY, pleadings. This is a technical word which must be introduced 
into every indictment for a felony, charging the offence to have been 
committed feloniously; no other word, nor any circumlocution, will supply 
its place. Com. Dig. Indictment, G 6; Bac. Ab. Indictment, G 1; 2 Hale, 172, 
184; Hawk. B. 2. c. 25, s. 55 Cro. C. C. 37; Burn's Just. Indict. ix.; 
Williams' Just. Indict. iv., Cro. Eliz. 193; 5 Co. 121; 1 Chit. Cr. Law, 
242.

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