A trait is an abstract, usually numerical representation of a quality possessed by a character. The term is used in all non-d20 System White Wolf games. It is equivalent to "stat" (short for "statistic") or "characteristic" in other roleplaying games.
Traits are usually grouped into types. The most common are Attributes, Abilities (in the Storyteller System and Revised Storyteller systems) or Skills (in the Storytelling System), and Advantages.
Most traits are rating from 1 to 5 dots, though some may be rated out of 10. The Storytelling System features some traits, like Size and derived traits like Speed, which are represented simply as numbers rather than dots.