Source : Webster's Revised Unabridged Dictionary (1913)

Ethically \Eth"ic*al*ly\, adv.
   According to, in harmony with, moral principles or character.

Source : WordNet®

ethically
     adv : in an ethical manner; from an ethical point of view;
           according to ethics; "he behaved ethically"; "this is
           ethically unacceptable" [ant: {unethically}]