Word Study
catadromous
CIDE DICTIONARY
catadromous, a. [Gr. kata` down + dro`mos a running.].
- 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] - Living in fresh water, and going to the sea to spawn; -- opposed to
anadromous , and said of the eel. [1913 Webster]
OXFORD DICTIONARY
catadromous, adj. (of a fish, e.g. the eel) that swims down rivers to the sea to spawn (cf. ANADROMOUS).
Etymology
Gk katadromos f. kata down + dromos running
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