A penis (cock) fatter than it is long; an utterly useless thing that no one could be proud of.
'My kid is a total choad; she called the principal at her school dad.'
is a choad.
'Mmmm fuck... Dude my choad is really itchy, do you mind if i scratch it?'
Some Paedophiles will settle for a choad.
He came to think of his choad as his off button.