Dilcue is the reverse of "Euclid" the early Greek founder of geometry. Typically this phrase is used as a name to insult someone for doing things backwards or completely improperly without regard for logic and reason.
This phrase is becoming increasing common, and is equivalent to calling someone a "dipshit" in an educated, yet geeky sense.
At the turn of the millennium, late 2000, this phrase became popular with older high school math teachers who had the desire to insult their students' failings with nonsensical jargon. This phrase, of course, sounds much dirtier than intended and caught on with attentive students.
"Chris you Dilcue! You installed the flux capacitor upside-down!"
"He played that banana like an electric guitar?? What a Dilcue!"