a. [ Gr. kata` down + dro`mos a running. ] 1. (Bot.) Having the lowest inferior segment of a pinna nearer the rachis than the lowest superior one; -- said of a mode of branching in ferns, and opposed to anadromous. [ 1913 Webster ]
2. (Zool.) Living in fresh water, and going to the sea to spawn; -- opposed to anadromous, and said of the eel. [ 1913 Webster ]