the GNU version of the Collaborative International Dictionary of English
ad. In a frightful manner; to a frightful dagree.
The Century Dictionary and Cyclopedia
In a frightful manner; dreadfully; terribly.
Intolerably; shockingly; hideously; exceedingly.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
ad. used as intensifiers
Word Usage
"Their outlook towards a venomous German attempt to do something "frightfully" nasty, is very similar to a large and powerful nurse dealing with a fractious child -- sort of: "Now, then, Master Frankie, you mustn't kick and scream like that.""