1630s, from Medieval Latin contemporarius, from Latin com- "with" (see com-) + temporarius "of time," from tempus "time" (see temporal (v.)). Meaning "modern, characteristic of the present" is from 1866.[contemporary etymology, contemporary origin, 英语词源]
"one who lives at the same time as another," 1630s, originally cotemporary, from co- + temporary; modified by influence of contemporary (adj.). Replacing native time-fellow (1570s).