means Happening once a week, or done, published, or recurring at intervals of seven days.

from From Old English wicu ("week") plus the adjective-and-adverb ending -ly, which descends from līc, meaning "body" or "form" — so "weekly" once carried the sense of "having the form of a week." The week itself is older than English, a seven-day rhythm long linked to the seven classical "planets" the ancients tracked, which is why our day-names still echo the sun, moon, and gods of those wandering lights.