as an abbreviation in Roman history in reckoning of dates it represent either ab urbe condita (q.v.) "from the founding of the city" or Anno Urbis Conditae "in the year of the founded city," from ablative of annus "year" (see annual (adj.)) + genitive of urbs "city" (see urban) + genitive of condita, fem. of conditus, past participle of condere "to set up, put together" (see abscond)
Entries linking to a.u.c.
ab urbe condita
with year-dates, an occasional Roman method of identifying a given year by reference to the time passed since founding of the city, which in 1c. B.C.E. was calculated to have taken place in what we would call 753 B.C.E. Literally "from the city founded;" the elements are ab "from" (see ab-) + ablative of urbs "city" (see urban) + fem. past participle of condere "put together, store," from assimilated form of com- "together" (see com-) + -dere "put" (from PIE root *dhe- "to put, place").
annual adj.
late 14c., "appointed by the year;" c. 1400, "occurring or done once a year," from Old French annuel "yearly" (12c.) or directly from Medieval Latin annualis "yearly," corresponding to Latin annalis as adjective form of annus "year."
This is reconstructed to be from Proto-Italic *atno- "year" (compare Oscan akno- "year, holiday, time of offering"), from PIE *at-no- "which goes," also "a year" (as "going around"), suffixed form of root *at- "to go" (source also of Sanskrit atati "goes, wanders," atamana- "to travel, wander," atya- "steed, runner"). The root also has Germanic derivatives meaning "a year," such as Gothic aþnam (dative plural) "year."
ab urbe conditaannual (adj.)urban (adj.)abscond (v.)