The Collaborative International Dictionary of English v.0.48:
Herbarium \Her*ba"ri*um\, n.; pl. E. Herbariums, L. Herbaria. [LL., fr. L. herba. See Herb, and cf. Arbor, Herbary.] 1. A collection of dried specimens of plants, systematically arranged. --Gray. [1913 Webster] 2. A book or case for preserving dried plants. [1913 Webster]