noun

1. The act of comparing or the state or process of being compared.

   “to bring a thing into comparison with another;  there is no comparison between them”

2. An evaluation of the similarities and differences of one or more things relative to some other or each-other.

   “He made a careful comparison of the available products before buying anything.”

3. With a negation, the state of being similar or alike.

   “There really is no comparison between the performance of today's computers and those of a decade ago.”