"Dinky" basically means "trivial" to me (a Canadian.) Not quite inconsequential—it can do something useful—it just does something simple enough that a person with experience in the language wouldn't even book time to accomplish it.

There's a piece of GTD advice—any task that would take you three minutes or less, just do it right when you think of it instead of putting it in your to-do list. One might describe those as "dinky tasks."