Ter"rane (?), n. [F. terrain, from L. terra earth.] (Geol.)
A group of rocks having a common age or origin; -- nearly equivalent to formation, but used somewhat less comprehensively.
© Webster 1913
Ter"rane, n. (Geog.)
A region or limited area considered with reference to some special feature; as, the terrane of a river, that is, its drainage basin.
© Webster 1913