What is language? a means to communicate your feelings, emotions to others. This the basic form of language we see in all animals alike. Humans beings are capable of naming the objects around them, this is the leap that made humans so different and this is what Allah used as a favor and evidence of His divinity.
Language is nothing but a specific formulation of voice, we can create lot of these voices to name objects, compendium of feelings etc. Words are nothings specific voices developed by a specific group of people to do above mentioned tasks.
Arabic was formed in this primitive and pure way.
other languages like urdu, english, were formed by accepting words from other languages and culmination of different words from languages are then slightly altered due to the dialect of the people hence making them part of that particular language
in short, arabic is one of original languages formed by making words from voices