Definitions for "Time of concentration"
The time required for water to flow from the farthest point on the watershed to the gaging station.
the time it takes for surface runoff to travel from the hydraulically farthest portion of the watershed to the design point.
The time it takes for runoff to travel from the hydraulically most distant point of a watershed until it reaches an outlet or other specified point within the watershed. It is used to estimate peak discharge or to develop a hydrograph. The time includes sheet flow, shallow concentrated flow, and channel flow.
time at which outflow from a basin is equal to inflow or time of equilibrium.