conventional or arbitrary relationship between language and the world.
Part of the word meaning is the reference.1.2 Concept
Though meaning and concept are closely related, they belong to different categories: concept is the result of human cognition while meaning is the result of language use.
1.3 Sense
Sense denotes the intrinsic semantic relationship inside the language. It is not concerned with the connection between words and what these words indicate in the word. The sense of an expression is its place in a system of semantic relationships with other expressions in the language.