In mathematics, a binary relationR is transitive if xRy and yRz together imply xRz. For example, the less-than relation is transitive. See transitivity.
In mathematics, a group action is transitive if it has just one orbit. It is called doubly transitive if it is transitive on ordered pairs of distinct elements; and so on for triply transitive, etc.. An ergodic group action is also called metrically transitive.