A three wheeled cycle used by mentally challenged to pick up cans and slow down traffic. Often trademarked by orange flags, a bell, personalized license plates, and a basket on back.
That retard needs to get his 3-tard off the road.
Someone who repeatedly signs up for a contract with '3' mobile phone network despite their having virtually no network cover and the worst customer service known to man.
"My sister, Claire, is a complete 3tard. She's just signed up for another two years with '3' even though she gets no signal within 40 miles of her home."