Co`in*cide" (?), v. i. [imp. & p. p. Coincided (?); p. pr. & vb. n. Coinciding.] [L. co- + incidere to fall on; in + cadere to fall: cf. F. coïncider. See Chance, n.] 1. To occupy the same place in space, as two equal triangles, when placed one on the other.

If the equator and the ecliptic had coincided, it would have rendered the annual revoluton of the earth useless.
Cheyne.

2. To occur at the same time; to be contemporaneous; as, the fall of Granada coincided with the discovery of America.

3. To correspond exactly; to agree; to concur; as, our aims coincide.

The rules of right jugdment and of good ratiocination often coincide with each other.
Watts.

• To occupy exactly the same space.
       The two squares coincide nicely.
  
• To occur at the same time.
       The conference will coincide with his vacation.
  
• To correspond, concur, or agree.
       Our ideas coincide, except in certain areas.