c. 1600, "a combining or joining together," from French conjoncture (16c.), from Medieval Latin coniunctura, from Latin coniunctus, past participle of coniugere "to join together," from assimilated form of com "with, together" (see con-) + iungere "to join together" (from nasalized form of PIE root *yeug- "to join"). Meaning "combination of circumstances," especially "a critical state of affairs," is from 1610s.