a dilly doof is someone that is remarkably silly or stupid in a funny way. Take the old english word for remarkable, dilly and combine it with the german doof (short for doofus), or a stupid person, and you have a remarkably silly person, a dilly doof.
Think of the main character in the movie Elf, 'oh nooo, I am such a dilly doof'. A husband that forgets to put down the toilet seat, 'dammit I am such a dilly doof'. Guy locks himself out of his own car... mumbles 'dilly doof' under his breath.
A silly/goofy looking person, place or thing
Look at that dogs haircut. He looks like a hoof doof!
A silly, goofy person. An airhead. Funny looking.
Look at that dog. Looks like a hoof doof!
An internalized beat or rhythm following a multiple-day-festival, which persists in the mind of a person for sometime after the music has ended.
Gary is usually a straight talker and square walker but given the pulsing pelvic thrusts and deep hip gyrations that flourish from his every step, I'd say that fella has a hint of doof residue still in his system.
When looks could kill
Pandabuy haul came in, I been Dr. Doofing.