.

In geometry, two points are called coincident when they are actually the same point as each other.[1] The same word has also been used more generally to other forms of incidence or special position between geometric objects.[2]

References

E.g. see Cormen, Thomas H.; Leiserson, Charles E., Rivest, Ronald L., Stein, Clifford (2009) [1990]. Introduction to Algorithms (3rd ed.). MIT Press and McGraw-Hill. ISBN 0-262-03384-4..
Weisstein, Eric W., "Coincident", MathWorld.