1. a group of individuals or vital statistics about them having a statistical factor in common, such as age class 2. silviculture a group of trees developing after a single disturbance, commonly consisting of trees of similar age, although it can include a considerable range of tree ages of seedling or sprout origin and trees that predate the disturbance —see age class, effective age, multiaged (multicohort) standThis definition last updated 10/25/2008