what is the transitive property?

Example:  "larger than" is a transitive property.

If A is larger than B and B is larger than C then A is larger than C.

Example of non-transitive property: "mother of" 

If A is mother of B and B is mother of C then A is not mother of C.

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According to this site

Transitive Property of Equality.

If one value (a) is equal to another value (b), which is equal to another value (c), then the first value (a) is equal to the third value ...

I have never heard of the term before.   

Thanks Alan, now it makes sense!