contemporaneous

/kənˈtɛmpəˌreɪniəs/

If you're born on the same day as your friend, you've got a contemporaneous birthday, or one that happens in the same period of time.

Contemporaneous comes from the Latin prefix con- meaning "together with" and temporaneus, meaning "time." Two contemporaneous events happen together in time. Richard Nixon's presidency and the first man on the moon are contemporaneous — both happened at the same period of time in history.

Definitions of contemporaneous

1. adjective

   occurring in the same period of time
   “a rise in interest rates is often contemporaneous with an increase in inflation”

   synonyms: contemporary

   synchronal, synchronic, synchronous

   occurring or existing at the same time or having the same period or phase
2. adjective

   of the same period
   synonyms: coetaneous, coeval

   synchronal, synchronic, synchronous

   occurring or existing at the same time or having the same period or phase