Question:

The resistance-per-length of the wire is wire's resistivity.

Answer:

Resistivity has units of ohms per meter therefore as regards wire it is certainly natural to assume that resistivity is a measure of the resistance per length of the wire. Such reasoning is called as dimensional analysis and quite habitually can be used to recall a formula. For example speed has units of meters per second. The meter is a calculate of distance and the second a measure of time so one can (correctly in this case) conclude that speed is distance-per-time.

In the condition of resistivity dimensional analysis initiate an incorrect conclusion. The Resistivity is resistance times length-per-area which has the same units as resistance-per-length but is not the same thing. One who recognizes that resistivity is a characteristic of a substance and not of an object could judge the statement to be false in that resistance-per-length would depend on how thick the wire is (a dimension of the object) not just on what material the wire is made of.