Dictionary.net

• To grieve: to sadden. "How then could I write when it was impossible but to attrist you! when I could speak of nothing but unparalleled horrors." - H. Walpole.

1899 - The american dictionary of the english language.
By Daniel Lyons

• at-trist', v.t. (obs.) to sadden. [Fr.--L. ad, to, tristis, sad.]

1908 - Chambers's Twentieth Century Dictionary of the English Language
By Thomas Davidson