The guy that knocked you up and either bailed or you kicked him to the curb. Not involved in the child's life except maybe enforced support payments. If you're a dude, what the baby mama calls you.
Tiffany met her bio-dad for the first time last week. Her first reaction was "What was Mom thinking?"
A trip to a grocery store, convenience store, or gas station for the sole purpose of buying an excessive amount of junk food and sugary drinks, usually with friends. A chud run often happens late at night and ends with everyone involved hating themselves afterwards.