What is the first characteristic of language?

It's impossible to say definitively what the "first" characteristic of language is, as they are all interconnected and fundamental. However, a strong contender for the most fundamental characteristic of language is its systematic nature.

Here's why:

* Structure and Rules: Language is not just a random collection of sounds or symbols. It has a structured system of rules (grammar, syntax, phonology) that govern how sounds, words, and sentences are combined. This system allows for meaning to be conveyed and understood.

* Shared Understanding: The systematic nature of language allows for a shared understanding between speakers. Because of the underlying rules, we can understand each other even though we may use different words or sentence structures.

* Evolution and Adaptation: The systematic nature of language also allows for it to evolve and adapt over time. New words and phrases are created, and the rules of grammar can change.

While other characteristics like meaningfulness, arbitrariness, and displacement are crucial to language, the systematic nature underpins all of them. It provides the framework for language to exist, evolve, and be understood.