an unfortunate fella who has no dad and survives solely of off pigeon comfort

A small marijuana cigarette. A poor boys joint - Tiny Tim would smoke one of these.

that quiet kid that always gets left behind especially in dangerous situations

A timmy is that one kid to break something at a party. He spills his drink at every dinner. If there is fire around, he will put his finger in it. If there is a knife around he will start cutting things.

The act of having someone else's workload pushed off on you. Usually when your unsure of the details to complete the job. Another term for being lazy!

Timmy is an average kid who no one understands, his mom dad and baby sitter all give him commands

Refers to a result of plus 2 to par (or worse ) on a golf hole (aka double bogey, triple bogey, etc.). Also, a player who has 3 or more putts on a hole has committed a Timmy.

Origin - Timmy is a guy that bailed on a golf commitment in the 11th hour. A scoundrel.