Abstrusely
The Century Dictionary and Cyclopedia
In an abstruse or recondite manner; in a manner not to be easily understood.
the GNU version of the Collaborative International Dictionary of English
adverb.
In an abstruse manner.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
adverb.
in a manner difficult to understand
Word Usage
"While the history of '00s New York dance-rock tilts toward the Rapture and LCD Soundsystem, the band known abstrusely as !!!"