Emily Dickinson Lexicon

CHASTE, a. [Fr. chaste; Arm. chast; It. Sp. and Port. casto; from L. castus. Sax. cuse, D. kuisch, G. keusch, Sw. kysk, Russ. chistei, are probably from the same root. Qu. Ir. caidh. I suppose the primary sense to be, separate, from the Oriental practice of sequestering females. If so, castus accords with the root of castle, W. câs; and at any rate, the word denotes purity, a sense taken from separation.]

1. Pure from all unlawful commerce of sexes. Applied to persons before marriage, it signifies pure from all sexual commerce, undefiled; applied to married persons, true to the marriage bed.
2. Free from obscenity. While they behold your chaste conversation – 1 Pet iii.
3. In language, pure; genuine; uncorrupt; free from barbarous words and phrases, and from quaint, affected, extravagant expressions.