The Collaborative International Dictionary of English v.0.48:
Ceremonially \Cer`e*mo"ni*al*ly\, adv. According to rites and ceremonies; as, a person ceremonially unclean. [1913 Webster]WordNet (r) 3.0 (2006):
ceremonially adv 1: in a ceremonious manner; "my mother advised her children ceremoniously" [syn: ceremoniously, ceremonially] [ant: unceremoniously] 2: in a ceremonial manner; "he was ceremonially sworn in as President" [syn: ceremonially, ritually]