The word in statistics is correlation.
Let's say there are two multi-dimensional entities A and B.
In order to find their similarities, we need to be able to observe and compare their dimensions. But what is a dimension, except thro the information emanating from an entity.
We correlate their information to find similarities, dependencies or interdependencies. If their information is highly correlated, we would say they have a high degree of similarities.
In social and behavioural science, you will also hear behavioural analysts say that someone's mental and behavioural characteristics correlate highly to a particular mental or developmental disorder.
Or biological pathologists saying that a particular outbreak has been closely correlated to a previously encountered strain, so much that they are similar or the same strain.
Perhaps, even when your friends joke about a disliked colleague, "Her behaviour correlates closely to that of a <<unkind word>>."