combine
The term you are looking for is "congregation," which refers to a group of similar things or people coming together.
Rug or carpet means similar things to mat.
Arrange, analyze
Aggregation is a group of varied things or a mass made up of distinct parts. Generalization is a group of similar things, but not identical things.
Analogy.
To classify means to categorize or group similar things together based on common characteristics or attributes. It helps in organizing and making sense of information by creating clear divisions or categories.
The English word "dozen" is derived from the French "douzaine", meaning "a group of twelve things". Similar words exist in French for "quinzaine" (a group of 15), "vingtaine" (20) and "centaine" (100), though these do not have English equivalents.
similarities mean things that are alike or similar in meaning.
A category is a group of people or things with shared characteristics or features.
the goals of systematic is to organize living things into group that have biological meaning.
A caboodle is an informal word meaning "a lot, group, crowd, collection of things". It is commonly used in the phrase "whole kit & caboodle" meaning everything or a collection of things.