Dictionary entry

Whilom

Webster's Dictionary 1913

Whi″lom (hwī″lŭm), adv. [AS. hwīlum, properly, at times, dative pl. of hwīl; akin to G. weiland formerly, OHG. hwīlōm, See While, n.] Formerly; once; of old; erewhile; at times. Spenser.

Whilom, as olde stories tellen us,

There was a duke that highte Theseus. Chaucer.